subject:(Solidification Alloys)

University of Tennessee – Knoxville

1. Gewecke, Nicholas Ray. Dynamics of Mushy Layers on a Finite Domain.

Degree: 2011, University of Tennessee – Knoxville

URL: https://trace.tennessee.edu/utk_graddiss/973

► p, li { white-space: pre-wrap; } Mushy layers are regions of intermixed liquid and solid which can arise during the solidification of binary alloys, generally… (more)

Subjects/Keywords: solidification; alloys; Other Applied Mathematics

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APA (6^th Edition):

Gewecke, N. R. (2011). Dynamics of Mushy Layers on a Finite Domain. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/973

Chicago Manual of Style (16^th Edition):

Gewecke, Nicholas Ray. “Dynamics of Mushy Layers on a Finite Domain.” 2011. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed January 23, 2021. https://trace.tennessee.edu/utk_graddiss/973.

MLA Handbook (7^th Edition):

Gewecke, Nicholas Ray. “Dynamics of Mushy Layers on a Finite Domain.” 2011. Web. 23 Jan 2021.

Vancouver:

Gewecke NR. Dynamics of Mushy Layers on a Finite Domain. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2011. [cited 2021 Jan 23]. Available from: https://trace.tennessee.edu/utk_graddiss/973.

Council of Science Editors:

Gewecke NR. Dynamics of Mushy Layers on a Finite Domain. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2011. Available from: https://trace.tennessee.edu/utk_graddiss/973

University of Arizona

2. Vaughn, Glen Allen. SOLIDIFICATION OF NICKEL-BASE ALLOYS CONTAINING TITANIUM AND ALUMINUM .

Degree: 1978, University of Arizona

URL: http://hdl.handle.net/10150/298843

Subjects/Keywords: Nickel alloys.; Solidification.

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APA (6^th Edition):

Vaughn, G. A. (1978). SOLIDIFICATION OF NICKEL-BASE ALLOYS CONTAINING TITANIUM AND ALUMINUM . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/298843

Chicago Manual of Style (16^th Edition):

Vaughn, Glen Allen. “SOLIDIFICATION OF NICKEL-BASE ALLOYS CONTAINING TITANIUM AND ALUMINUM .” 1978. Doctoral Dissertation, University of Arizona. Accessed January 23, 2021. http://hdl.handle.net/10150/298843.

MLA Handbook (7^th Edition):

Vaughn, Glen Allen. “SOLIDIFICATION OF NICKEL-BASE ALLOYS CONTAINING TITANIUM AND ALUMINUM .” 1978. Web. 23 Jan 2021.

Vancouver:

Vaughn GA. SOLIDIFICATION OF NICKEL-BASE ALLOYS CONTAINING TITANIUM AND ALUMINUM . [Internet] [Doctoral dissertation]. University of Arizona; 1978. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10150/298843.

Council of Science Editors:

Vaughn GA. SOLIDIFICATION OF NICKEL-BASE ALLOYS CONTAINING TITANIUM AND ALUMINUM . [Doctoral Dissertation]. University of Arizona; 1978. Available from: http://hdl.handle.net/10150/298843

Indian Institute of Science

3. Chakraborty, Prodyut Ranjan. Single-Phase And Multi-Phase Convection During Solidification Of Non-eutectic Binary Solutions.

Degree: PhD, Faculty of Engineering, 2014, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/2404

► During solidification of non-eutectic alloys, non-isothermal phase change causes dendritic growth of solid front with liquid phase entrapped within the dendritic network producing the mushy… (more)

▼ During solidification of non-eutectic alloys, non-isothermal phase change causes dendritic growth of solid front with liquid phase entrapped within the dendritic network producing the mushy region. Solidification causes rejection of solute at the solid-liquid interface and within the mushy zone, causing a sharp concentration gradient to build up across the mushy region. At the same time, a temperature gradient is present as a result of externally imposed boundary conditions as well as due to evolution of latent heat, giving rise to the so-called “double-diffusive” or thermo-solutal convection. Depending on the relative density of the solute being rejected in the liquid phase during solidification process, thermal and solutal buoyancy can either aid or oppose each other. Rejection of a heavier solute leads to aiding thermo-solutal convection situation whereas the rejection of lighter solute causes the thermal and solutal buoyancy to oppose each other. If the thermal and solutal buoyancies oppose each other, flow instability arises adjacent to the mush-bulk liquid interface regions. Thus, there may be a wide variety of convection situations present in the solidifying domain for different combinations of solution concentrations and externally imposed boundary conditions. The situation becomes even more complex if the solid phase movement along with the bulk flow is involved in the process, leading to multiphase convection. Detachment of solid phase from the solid/liquid interface can be caused by remelting (solutal and/or thermal) and shearing action of a convecting liquid adjacent to the interface. Depending on the drag of the bulk flow and the density of the solid phase relative to that of the bulk liquid, these detached particles can either float or sediment. The redistribution of the rejected solute by means of diffusion (at a local scale) and thermo-solutal convection (at system level length scales) causes heterogeneous orientation of mixture constituents over the solidifying domain popularly known as macro-segregation. From the point of view of manufacturing, severe form of macro-segregation or heterogeneous species distribution is an undesirable phenomenon and hence, a thorough understanding of the species redistribution by means of diffusion and convection during solidification process is very important. Most of the earlier studies on double diffusive convection during solidification involved fixed dendrites. However, the advection of solid particles during the solidification process can generate major instability in the flow pattern while modifying the solid front growth, and hence the macro-segregation pattern considerably. With this viewpoint in mind, the overall objective of the present work is to address these wide-varieties of single phase and multi phase flow situations and their effect on solid front growth and macro-segregation during directional solidification of non-eutectic binary alloys, numerically as well as experimentally. Different configurations of directional solidification… Advisors/Committee Members: Dutta, Pradip (advisor).

Subjects/Keywords: Convection (Heat Engineering); Solidification; Non-eutectic Alloys; Non-Eutectic Binary Alloys - Solidification; Alloy Solidification - Modelling; Singlephase Convection; Multiphase Convection; Metallurgy

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Chakraborty, P. R. (2014). Single-Phase And Multi-Phase Convection During Solidification Of Non-eutectic Binary Solutions. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2404

Chicago Manual of Style (16^th Edition):

Chakraborty, Prodyut Ranjan. “Single-Phase And Multi-Phase Convection During Solidification Of Non-eutectic Binary Solutions.” 2014. Doctoral Dissertation, Indian Institute of Science. Accessed January 23, 2021. http://etd.iisc.ac.in/handle/2005/2404.

MLA Handbook (7^th Edition):

Chakraborty, Prodyut Ranjan. “Single-Phase And Multi-Phase Convection During Solidification Of Non-eutectic Binary Solutions.” 2014. Web. 23 Jan 2021.

Vancouver:

Chakraborty PR. Single-Phase And Multi-Phase Convection During Solidification Of Non-eutectic Binary Solutions. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2014. [cited 2021 Jan 23]. Available from: http://etd.iisc.ac.in/handle/2005/2404.

Council of Science Editors:

Chakraborty PR. Single-Phase And Multi-Phase Convection During Solidification Of Non-eutectic Binary Solutions. [Doctoral Dissertation]. Indian Institute of Science; 2014. Available from: http://etd.iisc.ac.in/handle/2005/2404

Cape Peninsula University of Technology

4. Rzyankina, Ekaterina. Numerical and experimental investigation of directional solidification in vacuum investment casting of superalloys .

Degree: 2013, Cape Peninsula University of Technology

URL: http://etd.cput.ac.za/handle/20.500.11838/1243

► High temperatures encountered in combustion chambers of jet engines has demanded the creation of new technologies and new materials for the construction of one of… (more)

▼ High temperatures encountered in combustion chambers of jet engines has demanded the creation of new technologies and new materials for the construction of one of the most critical elements of these systems - the stator and rotor turbine blades. They have to withstand extreme temperatures for extended periods without the loss of mechanical strength, conditions under which many steels and alloys fail. Such failure is ascribed to the combination of high temperatures and high centrifugal forces, resulting in creep. The high temperature creep mechanism of grain boundary sliding has limited the operation capability of fine-grained equiaxed castings. Higher operating temperatures were achieved with higher alloy contents and coarse-grained equiaxed castings. This is especially prevalent in multi-crystalline structures in which grain boundaries present weaknesses in the structure. However, notwithstanding these improvements, high temperature resistant alloys formed as single crystal structures offer the necessary material properties for safe performance under these extreme conditions. Damage to turbine blade surfaces is often caused by oxidation and hot corrosion. For this reason, turbine blades are coated with a thermal barrier coating (TBC), which consists of ceramic materials that reduce the heat flux through the airfoil. In this research work, modelling and simulation techniques were initially used to study the directional solidification (DS) of crystal structures during vacuum investment casting. The modelling of the solidification process was implemented using a Finite Element casting simulation software, ProCAST, to predict thermal and flow profiles. These models allowed the study of the dendritic growth rate, the formation of new grains ahead of the solid/liquid interface and the morphology of the dendritic microstructure. These studies indicated the opportunity to optimise the velocity of the solidification front (solidification rate) for single crystal structures. The aim of this research was therefore to investigate the effect of the solidification rate (or withdrawal velocity) on the quality of SC castings. The investigations were carried out for nickel-based superalloy CMSX-4 turbine blade casts and rods using the Bridgman process for vacuum investment casting. The SC castings were heat treated to improve the grain structure for enhanced creep resistance. The heat treated SC castings were inspected by X-ray diffraction to analyse crystallographic orientation and chemical composition; and by SEM, OP (optical microscopy) and microprobe analysis to analyse the microstructure; in addition to macrostructural investigations. In the experimental analysis, the formation of new grains ahead of the solidi/liquid interface and the effect of dendrite packing patterns on the primary dendrite spacing were investigated. Creep tests were conducted to compare the creep properties of the SC castings for different withdrawal rates, and to draw conclusions regarding the effect of withdrawal rate on the microstructure (and hence the…

Subjects/Keywords: Directional solidification; Alloys – Metallurgy; Heat resistant alloys; Dissertations, Academic; MTech

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APA (6^th Edition):

Rzyankina, E. (2013). Numerical and experimental investigation of directional solidification in vacuum investment casting of superalloys . (Thesis). Cape Peninsula University of Technology. Retrieved from http://etd.cput.ac.za/handle/20.500.11838/1243

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Rzyankina, Ekaterina. “Numerical and experimental investigation of directional solidification in vacuum investment casting of superalloys .” 2013. Thesis, Cape Peninsula University of Technology. Accessed January 23, 2021. http://etd.cput.ac.za/handle/20.500.11838/1243.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Rzyankina, Ekaterina. “Numerical and experimental investigation of directional solidification in vacuum investment casting of superalloys .” 2013. Web. 23 Jan 2021.

Vancouver:

Rzyankina E. Numerical and experimental investigation of directional solidification in vacuum investment casting of superalloys . [Internet] [Thesis]. Cape Peninsula University of Technology; 2013. [cited 2021 Jan 23]. Available from: http://etd.cput.ac.za/handle/20.500.11838/1243.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Rzyankina E. Numerical and experimental investigation of directional solidification in vacuum investment casting of superalloys . [Thesis]. Cape Peninsula University of Technology; 2013. Available from: http://etd.cput.ac.za/handle/20.500.11838/1243

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

5. Zollinger, Julien. Influence de l'oxygène sur le comportement à la solidification d'aluminiures de titane binaires et alliés au niobium basés sur le composé intermétallique [gamma]-TiAI : Influence of oxygen on the solidification behaviour of binary and niobium containing gamma titanium aluminides.

Degree: Docteur es, Science et ingénierie des matériaux, 2008, Lorraine INP

URL: http://www.theses.fr/2008INPL032N

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Cette étude s’inscrit dans le cadre du projet européen IMPRESS, "Intermetallic Materials Processing in Relation to Earth and Space Solidification". Elle porte sur la compréhension… (more)

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Cette étude s’inscrit dans le cadre du projet européen IMPRESS, "Intermetallic Materials Processing in Relation to Earth and Space Solidification". Elle porte sur la compréhension des mécanismes fondamentaux qui contrôlent la solidification de l’alliage Ti-46Al-8Nb envisagés pour le développement d’aubes de turbines. La première partie de cette étude caractérise l’influence de l’oxygène sur le comportement à la solidification d’alliages de base TiAl coulés et contenant de 40 a 48 at.% d’aluminium. L’addition d’oxygène augmente la fraction volumique de phase [alpha] formée pendant la solidification péritectique et conduit au changement de la phase primaire de solidification de la phase [bêta] à la phase [alpha] dans les alliages ternaires Ti-44,3Al-1,5O, Ti-47,7Al-0,8O et Ti-47,3Al-1,5O (at.%). Les coefficients de partage pour l’aluminium et l’oxygène kAl[alpha]/l= 0,9 et kO[alpha]/l = 1,29, ont été déterminés pour l’alliage ayant [alpha] comme phase primaire de solidification. Dans un deuxième temps, l’étude du comportement à la solidification de l’alliage Ti-46Al-8Nb, est décrite en portant une attention particulière sur les effets de la contamination et des conditions de croissance sur la formation des microstructures et des microségrégations. Deux comportements différents ont été mis en évidence : dans la phase primaire de solidification [alpha] rencontrée pour des hauts niveaux de contamination en oxygène, une très faible rétrodiffusion est observée. Pour de faibles quantités d’oxygène, la phase primaire de solidification est la phase [bêta]. Dans ce cas la présence d’oxygène induit une augmentation de l’amplitude de ségrégation malgré une forte rétrodiffusion dans la structure cubique centrée

This study was performed in the framework of the IMPRESS, "Intermetallic Materials Processing in Relation to Earth and Space Solidification", and is dedicated to the understanding of the fundamental mechanisms that control solidification in a Ti-46Al-8Nb alloy selected for TiAl-based alloy turbine blade development. The first part of this work is devoted to study the influence of oxygen on the solidification behaviour of cast TiAl-based alloys containing from 40 to 48 at.% of Al. Increasing the oxygen content affects significantly the macrostructure of the as-cast ingots, increases volume fraction of the phase formed during the peritectic solidification and leads to a change of the [bêta] primary solidification phase to the [alpha] phase in the ternary Ti-44.2Al-1.4O, Ti-47.3Al-0.9O and Ti-47.2Al-1.5O (at.%) alloys. When [alpha] is the primary solidification phase, the partition coefficients has been determined as kAl[alpha]/l= 0,9 and kO(alpha]/l = 1,29. In a second part, the solidification behaviour of Ti-46Al-8Nb alloy is investigated, with a particular attention to the contamination and growth conditions effects on microstructures and microsegregation formations. For high contamination levels, the solidification phase is [alpha] where oxygen reduces solute mobility, leading to limited backdiffusion. In low oxygen…

Advisors/Committee Members: Combeau, Hervé (thesis director), Daloz, Dominique (thesis director).

Subjects/Keywords: Solidification; Microstructures; Microségrégation; Alliages TiAl; Composés intermétalliques; Solidification; Microstructures; Microsegregation; TiAl-based alloys; Intermetallic compounds

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zollinger, J. (2008). Influence de l'oxygène sur le comportement à la solidification d'aluminiures de titane binaires et alliés au niobium basés sur le composé intermétallique [gamma]-TiAI : Influence of oxygen on the solidification behaviour of binary and niobium containing gamma titanium aluminides. (Doctoral Dissertation). Lorraine INP. Retrieved from http://www.theses.fr/2008INPL032N

Chicago Manual of Style (16^th Edition):

Zollinger, Julien. “Influence de l'oxygène sur le comportement à la solidification d'aluminiures de titane binaires et alliés au niobium basés sur le composé intermétallique [gamma]-TiAI : Influence of oxygen on the solidification behaviour of binary and niobium containing gamma titanium aluminides.” 2008. Doctoral Dissertation, Lorraine INP. Accessed January 23, 2021. http://www.theses.fr/2008INPL032N.

MLA Handbook (7^th Edition):

Zollinger, Julien. “Influence de l'oxygène sur le comportement à la solidification d'aluminiures de titane binaires et alliés au niobium basés sur le composé intermétallique [gamma]-TiAI : Influence of oxygen on the solidification behaviour of binary and niobium containing gamma titanium aluminides.” 2008. Web. 23 Jan 2021.

Vancouver:

Zollinger J. Influence de l'oxygène sur le comportement à la solidification d'aluminiures de titane binaires et alliés au niobium basés sur le composé intermétallique [gamma]-TiAI : Influence of oxygen on the solidification behaviour of binary and niobium containing gamma titanium aluminides. [Internet] [Doctoral dissertation]. Lorraine INP; 2008. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2008INPL032N.

Council of Science Editors:

Zollinger J. Influence de l'oxygène sur le comportement à la solidification d'aluminiures de titane binaires et alliés au niobium basés sur le composé intermétallique [gamma]-TiAI : Influence of oxygen on the solidification behaviour of binary and niobium containing gamma titanium aluminides. [Doctoral Dissertation]. Lorraine INP; 2008. Available from: http://www.theses.fr/2008INPL032N

Northeastern University

6. Rezaeeyazdi, Mahboobeh. Understanding the effects of rapid solidification and ternary alloying additions on chemical order-disorder transformation in FeNi₃.

Degree: MS, Department of Chemical Engineering, 2016, Northeastern University

URL: http://hdl.handle.net/2047/D20201831

► Owing to their unusual thermal expansion behavior and good magnetic permeability characteristics, iron-nickel alloys are often at the cutting-edge of technology. Understanding the chemical order-disorder… (more)

Subjects/Keywords: rapid solidification; ternary alloying additions; Iron-nickel alloys; Properties; Order-disorder in alloys; Order-disorder models; Iron-nickel alloys; Rapid solidification processing; Ternary alloys; Chemical kinetics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rezaeeyazdi, M. (2016). Understanding the effects of rapid solidification and ternary alloying additions on chemical order-disorder transformation in FeNi₃. (Masters Thesis). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20201831

Chicago Manual of Style (16^th Edition):

Rezaeeyazdi, Mahboobeh. “Understanding the effects of rapid solidification and ternary alloying additions on chemical order-disorder transformation in FeNi₃.” 2016. Masters Thesis, Northeastern University. Accessed January 23, 2021. http://hdl.handle.net/2047/D20201831.

MLA Handbook (7^th Edition):

Rezaeeyazdi, Mahboobeh. “Understanding the effects of rapid solidification and ternary alloying additions on chemical order-disorder transformation in FeNi₃.” 2016. Web. 23 Jan 2021.

Vancouver:

Rezaeeyazdi M. Understanding the effects of rapid solidification and ternary alloying additions on chemical order-disorder transformation in FeNi₃. [Internet] [Masters thesis]. Northeastern University; 2016. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2047/D20201831.

Council of Science Editors:

Rezaeeyazdi M. Understanding the effects of rapid solidification and ternary alloying additions on chemical order-disorder transformation in FeNi₃. [Masters Thesis]. Northeastern University; 2016. Available from: http://hdl.handle.net/2047/D20201831

Universidade Estadual de Campinas

7. Duarte, Roberto Nunes, 1965-. Solidificação unidirecional transitória, microestrutura e propriedades termofísicas e mecânicas de ligas Al-Ag-(Cu): Transient unidirectional solidification, microstructure and thermophysical and mechanical properties of Al-Ag-(Cu) Alloys.

Degree: 2016, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/265704

► Abstract: Aluminum-based alloys are being increasingly applied in the manufacture of mechanical components replacing traditional metallic materials such as steel, with a view to reducing… (more)

▼ Abstract: Aluminum-based alloys are being increasingly applied in the manufacture of mechanical components replacing traditional metallic materials such as steel, with a view to reducing weight and to increasing corrosion resistance. As far as the application of these alloys in the automotive and aeronautics industries are concerned, the weight is considered a significant factor, since it is directly connected to energy consumption, and in this particular situation Al-based alloys surpass other alternative metallic materials with respect to the mechanical strength/weight ratio. Considering manufacturing processes that preserve the original solidification structure of components, or when they are subjected to surface remelting/re-solidification treatments, the microstructural parameters will play a determinant role in the final properties. By analyzing the literature, it is possible to verify that despite the existence of a variety of studies focusing on binary Al alloys, some systems, such as Al-Ag, have not been properly investigated despite the application potential of such alloys associated with their castability and workability. In this study, four hypoeutectic alloys and a ternary Al-Ag-Cu alloy were directionally solidified under unsteady-state heat flow conditions, which is the class of heat flow encompassing the majority of industrial solidification processes, and the microstructure evolution was analyzed. Thermal parameters such as the growth rate (VL), thermal gradient (GL) and the cooling rate (TR) were experimentally determined by the experimental cooling curves. A computational thermodynamics software was used for the characterization of the solidification paths and thermophysical properties, which have been subsequently used with the experimental temperature data in a numerical solidification model for the determination of transient metal/mold heat transfer coefficients. The solidification microstructure of all the alloys examined is shown to be characterized by an Al-matrix of dendritic morphology along the entire lengths of the castings. The primary dendritic arm spacing (?1) and the secondary arm spacing (?2) were measured and experimental growth laws relating ?1 and ?2 to VL e TR are proposed. The experimental dendritic spacings are compared with theoretical predictions furnished by unsteady-state growth models (Bouchard-Kirkaldy and Hunt-Lu). Hardness and tensile properties determined along the length of the directionally solidified Al-Ag alloys castings (that is, with increasing dendritic spacings from the cooled bottom to the top of the castings) have shown that the scale of such microstructural parameters do not affect the experimental values of such properties. However, both hardness and tensile properties increase with the increase in the alloy Ag content. In contrast, with the addition of 4.5%Cu to the Al-4.5%Ag alloy, the dendritic spacing is shown to affect significantly such mechanical properties, with maximum values of elongation to fracture and ultimate tensile strength (associated with… Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Cheung, Noé, 1974- (advisor), Garcia, Amauri, 1949- (advisor), Universidade Estadual de Campinas. Faculdade de Engenharia Mecânica (institution), Programa de Pós-Graduação em Engenharia Mecânica (nameofprogram), Spinelli, Jose Eduardo (committee member), Goulart, Pedro Roberto (committee member), Zavaglia, Cecília Amélia de Carvalho (committee member), Arruda, Antonio Celso Fonseca de (committee member).

Subjects/Keywords: Ligas de alumínio; Solidificação; Propriedades termofísicas; Aluminum alloys; Solidification; Thermophysical properties

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Duarte, Roberto Nunes, 1. (2016). Solidificação unidirecional transitória, microestrutura e propriedades termofísicas e mecânicas de ligas Al-Ag-(Cu): Transient unidirectional solidification, microstructure and thermophysical and mechanical properties of Al-Ag-(Cu) Alloys. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/265704

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Duarte, Roberto Nunes, 1965-. “Solidificação unidirecional transitória, microestrutura e propriedades termofísicas e mecânicas de ligas Al-Ag-(Cu): Transient unidirectional solidification, microstructure and thermophysical and mechanical properties of Al-Ag-(Cu) Alloys.” 2016. Thesis, Universidade Estadual de Campinas. Accessed January 23, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265704.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Duarte, Roberto Nunes, 1965-. “Solidificação unidirecional transitória, microestrutura e propriedades termofísicas e mecânicas de ligas Al-Ag-(Cu): Transient unidirectional solidification, microstructure and thermophysical and mechanical properties of Al-Ag-(Cu) Alloys.” 2016. Web. 23 Jan 2021.

Vancouver:

Duarte, Roberto Nunes 1. Solidificação unidirecional transitória, microestrutura e propriedades termofísicas e mecânicas de ligas Al-Ag-(Cu): Transient unidirectional solidification, microstructure and thermophysical and mechanical properties of Al-Ag-(Cu) Alloys. [Internet] [Thesis]. Universidade Estadual de Campinas; 2016. [cited 2021 Jan 23]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/265704.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Duarte, Roberto Nunes 1. Solidificação unidirecional transitória, microestrutura e propriedades termofísicas e mecânicas de ligas Al-Ag-(Cu): Transient unidirectional solidification, microstructure and thermophysical and mechanical properties of Al-Ag-(Cu) Alloys. [Thesis]. Universidade Estadual de Campinas; 2016. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/265704

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade Estadual de Campinas

8. Verissimo, Nathália Carolina, 1987-. Solidificação unidirecional de ligas Mg-Zn para aplicações biomédicas : evolução microestrutural, macrossegregação, dureza e resistência a corrosão: Unidirectional solidification of Mg-Zn alloys for biomedical applications : microstructural evolution, macrossegregation, hardness and corrosion resistance.

Degree: 2017, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/322100

► Abstract: Magnesium and its alloys are known as the lightest available structural metals, inducing new research in applications in the automotive, aerospace and biomaterial areas.… (more)

▼ Abstract: Magnesium and its alloys are known as the lightest available structural metals, inducing new research in applications in the automotive, aerospace and biomaterial areas. Mg and its alloys are considered as a new class of metal biomaterials, by their unique combination of properties, such as biocompatibility (biodegradability and bio-absorption) in physiological environments, and an excellent combination of mechanical properties when compared with polymers and ceramics. The electrochemical behavior of Mg-Zn alloys is influenced by microstructural characteristics, altering their behavior against corrosion. Experimental studies emphasizing factors related to the microstructure (chemical composition, cooling rate and growth rate), as well as its correlation with mechanical and chemical properties, are rare for Mg-Zn alloys. Thus, a deeper understanding of the microstructural evolution as a function of these parameters can be attained with the use of the unidirectional solidification technique, as it promotes a wide range of experimental values of thermal parameters in a single experiment. This will permit important characteristics such as: grain size, macrostructure, morphology and scale of the phases forming the microstructure and distribution of intermetallic phases to be analyzed. These microstructural parameters are determinant for the final mechanical and chemical properties, which consequently determine the processing conditions. In the present work, a wide range of experimental values of cooling rates was obtained by transient unidirectional solidification, and four different compositions of hypoeutectic alloys of the Mg-Zn system (2.5 to 25wt.% Zn) were studied. The macrostructures are characterized by fine equiaxed grains along the entire length of the ingots, and the microstructures are characterized by an ?-Mg phase dendritic matrix, eutectic and intermetallic phases. The primary dendritic spacing (?1) is correlated with the values of cooling rate (?) and growth rate (VL) through experimental laws and Vickers hardness profile (HV). The influence of intrinsic aspects of the microstructure is also examined with respect to the corrosion resistance Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Garcia, Amauri, 1949- (advisor), Cheung, Noé, 1974- (coadvisor), Universidade Estadual de Campinas. Faculdade de Engenharia Mecânica (institution), Programa de Pós-Graduação em Engenharia Mecânica (nameofprogram), Zavaglia, Cecília Amélia de Carvalho (committee member), Souza, Eduardo Netto de (committee member), González, Juan José de Damborenea (committee member), Sandor, Leonardo Taborda (committee member).

Subjects/Keywords: Microestrutura; Ligas; Biomateriais; Solidificação; Corrosão; Microstructure; Alloys; Biomaterials; Solidification; Corrosion

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Verissimo, Nathália Carolina, 1. (2017). Solidificação unidirecional de ligas Mg-Zn para aplicações biomédicas : evolução microestrutural, macrossegregação, dureza e resistência a corrosão: Unidirectional solidification of Mg-Zn alloys for biomedical applications : microstructural evolution, macrossegregation, hardness and corrosion resistance. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/322100

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Verissimo, Nathália Carolina, 1987-. “Solidificação unidirecional de ligas Mg-Zn para aplicações biomédicas : evolução microestrutural, macrossegregação, dureza e resistência a corrosão: Unidirectional solidification of Mg-Zn alloys for biomedical applications : microstructural evolution, macrossegregation, hardness and corrosion resistance.” 2017. Thesis, Universidade Estadual de Campinas. Accessed January 23, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/322100.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Verissimo, Nathália Carolina, 1987-. “Solidificação unidirecional de ligas Mg-Zn para aplicações biomédicas : evolução microestrutural, macrossegregação, dureza e resistência a corrosão: Unidirectional solidification of Mg-Zn alloys for biomedical applications : microstructural evolution, macrossegregation, hardness and corrosion resistance.” 2017. Web. 23 Jan 2021.

Vancouver:

Verissimo, Nathália Carolina 1. Solidificação unidirecional de ligas Mg-Zn para aplicações biomédicas : evolução microestrutural, macrossegregação, dureza e resistência a corrosão: Unidirectional solidification of Mg-Zn alloys for biomedical applications : microstructural evolution, macrossegregation, hardness and corrosion resistance. [Internet] [Thesis]. Universidade Estadual de Campinas; 2017. [cited 2021 Jan 23]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/322100.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Verissimo, Nathália Carolina 1. Solidificação unidirecional de ligas Mg-Zn para aplicações biomédicas : evolução microestrutural, macrossegregação, dureza e resistência a corrosão: Unidirectional solidification of Mg-Zn alloys for biomedical applications : microstructural evolution, macrossegregation, hardness and corrosion resistance. [Thesis]. Universidade Estadual de Campinas; 2017. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/322100

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade Estadual de Campinas

9. Moutinho, Daniel Joaquim da Conceição. Análise da evolução microestrutural e da formação de macrossegregação e microporosidade na solidificação unidirecional transitória de ligas ternárias Al-Cu-Si: Analysis of microestrutural evolution and formation of macrosegregation and microparasity in the unidirectional transient solidification of ternary Al-Cu-Si alloys.

Degree: 2012, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/264727

► Abstract: Aluminum alloys castings had a fundamental role in the growth of the metal-mechanics industry. Nowadays these alloys are supplied in a wide range of… (more)

▼ Abstract: Aluminum alloys castings had a fundamental role in the growth of the metal-mechanics industry. Nowadays these alloys are supplied in a wide range of chemical compositions. We highlight the Al-Cu-Si ternary system because of particular outstanding properties such as high mechanical strength, low weight and very good fluidity. These qualities make them a good choice for applications in the automotive and aerospace industry. The potential of such alloys has attracted much attention of researchers with a view to investigating the microstructure evolution, and the formation of macrosegregation and porosity during the solidification process. In the present work, the microstructures of Al-Cu-Si alloys are characterized and correlated with solidification thermal parameters. The evolutions of macrosegreation and porosity during transient solidification are also examined both experimentally and by numerical simulations. The dendritic microstructure has been characterized using current metallographic techniques for both Al6Cu1Si e Al6Cu4Si alloys and the interdendritic spacings were measured by methods found in the literature. The results have shown that the addition of silicon to the alloy composition decreases the primary and secondary dendritic spacing when compared with those of an Al6Cu alloy. Experimental laws describing the evolution of dendritic spacings with the cooling rate ( ? ) and the velocity of the liquidus isotherm (VL) are proposed, i.e., 'lambda IND. 1' = C ( ? )-0,55, 'lambda IND. 2' = C ( ? )-0,33 and 'lambda IND. 3' for the primary, secondary and tertiary dendritic spacings, respectively. The experimental results of secondary dendritic spacings have been compared with the predictions of the only theoretical model existing in the literature for dendritic growth of multicomponent alloys. The Thermo-Calc software has been used to yield the tertiary phase diagram, thermophysical properties and the solidification path for both alloys. The experimental and numerical macrosegregations profiles, as well as the theoretical and apparent densities are presented as a function of the castings lenghts. The solute profiles that occur during the transient unidirectional solidification were simulated taking into account the formation of secondary phases during solidification. The microporosity was determined using a pyknometry procedure. The work also shows that the use of a carbon steel chill plate induces an abnormal increase in porous fraction at regions close to the casting cooled surface caused by a higher iron content, due to diffusive flux of iron from the chill steel plate toward the casting surface Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Garcia, Amauri, 1949- (advisor), Ferreira, Ivaldo Leão (coadvisor), Universidade Estadual de Campinas. Faculdade de Engenharia Mecânica (institution), Programa de Pós-Graduação em Engenharia Mecânica (nameofprogram), Ierardi, Maria Clara Filippini (committee member), Zavaglia, Cecília Amélia de Carvalho (committee member), Spinelli, Jose Eduardo (committee member), Rocha, Otavio Fernandes Lima da (committee member).

Subjects/Keywords: Solidificação; Ligas de alumínio; Microestrutura; Solidification; Aluminum alloys; Microestructure

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Moutinho, D. J. d. C. (2012). Análise da evolução microestrutural e da formação de macrossegregação e microporosidade na solidificação unidirecional transitória de ligas ternárias Al-Cu-Si: Analysis of microestrutural evolution and formation of macrosegregation and microparasity in the unidirectional transient solidification of ternary Al-Cu-Si alloys. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/264727

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Moutinho, Daniel Joaquim da Conceição. “Análise da evolução microestrutural e da formação de macrossegregação e microporosidade na solidificação unidirecional transitória de ligas ternárias Al-Cu-Si: Analysis of microestrutural evolution and formation of macrosegregation and microparasity in the unidirectional transient solidification of ternary Al-Cu-Si alloys.” 2012. Thesis, Universidade Estadual de Campinas. Accessed January 23, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264727.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Moutinho, Daniel Joaquim da Conceição. “Análise da evolução microestrutural e da formação de macrossegregação e microporosidade na solidificação unidirecional transitória de ligas ternárias Al-Cu-Si: Analysis of microestrutural evolution and formation of macrosegregation and microparasity in the unidirectional transient solidification of ternary Al-Cu-Si alloys.” 2012. Web. 23 Jan 2021.

Vancouver:

Moutinho DJdC. Análise da evolução microestrutural e da formação de macrossegregação e microporosidade na solidificação unidirecional transitória de ligas ternárias Al-Cu-Si: Analysis of microestrutural evolution and formation of macrosegregation and microparasity in the unidirectional transient solidification of ternary Al-Cu-Si alloys. [Internet] [Thesis]. Universidade Estadual de Campinas; 2012. [cited 2021 Jan 23]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/264727.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Moutinho DJdC. Análise da evolução microestrutural e da formação de macrossegregação e microporosidade na solidificação unidirecional transitória de ligas ternárias Al-Cu-Si: Analysis of microestrutural evolution and formation of macrosegregation and microparasity in the unidirectional transient solidification of ternary Al-Cu-Si alloys. [Thesis]. Universidade Estadual de Campinas; 2012. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/264727

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade Estadual de Campinas

10. Gomes, Laercio Gouvea. Microestrutura dendrítica, macrossegregação e microporosidade na solidificação de ligas ternárias Al-Si-Cu: Dendritic microstructure, macrosegregation and microporosity in the solidification of ternary Al-Si-Cu alloys.

Degree: 2012, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/264725

► Abstract: Aluminum casting alloys have properties which are of great industrial interest, such as low density, good corrosion resistance, high thermal and electrical conductivities, good… (more)

▼ Abstract: Aluminum casting alloys have properties which are of great industrial interest, such as low density, good corrosion resistance, high thermal and electrical conductivities, good combination of mechanical properties, good workability in machining processes and mechanical forming. Currently, these alloys are produced in various systems and dozens of compositions. The literature presents several studies, both theoretical and experimental, focusing on the microstructural evolution of binary aluminum base alloys. Theoretical and experimental cellular and dendritic growth laws have been proposed and validated. Macrosegregation and pore formation during solidification of binary alloys of aluminum have been the focus of several recent studies. However, there are few studies in the literature addressing important families of multicomponent aluminum base alloys. Accordingly, this study aims to analyze Aluminum- Silicon-Copper alloys (series: A319.1 and A333.1) [Al-5.5wt%Si-3.0wt%Cu and Al-9.0wt%Si- 3.0wt%Cu] with respect to the evolution of the dendritic microstructure, porosity formation and macrosegregation during solidification. For the production of the ternary alloys commercially pure aluminum and silicon and electrolytic copper have been used. Solute macrosegregation and microporosity formation are investigated both experimentally and through numerical simulations. The dendritic microstructure is quantified by their primary, secondary and tertiary arm spacings, which are correlated with solidification thermal parameters. The solute macrosegregation profiles, theoretical and apparent densities have been determined along the castings lengths. The solute segregation profiles were obtained by X-ray fluorescence spectrometry and the simulations were performed taking into account secondary phase transformations that occur during solidification. Microporosity measurements were carried out by the picnometry technique...Note: The complete abstract is available with the full electronic document Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Garcia, Amauri, 1949- (advisor), Ferreira, Ivaldo Leão (coadvisor), Universidade Estadual de Campinas. Faculdade de Engenharia Mecânica (institution), Programa de Pós-Graduação em Engenharia Mecânica (nameofprogram), Ierardi, Maria Clara Filippini (committee member), Osorio, Wislei Riuper Ramos (committee member), Rocha, Otavio Fernandes Lima da (committee member), Spinelli, Jose Eduardo (committee member).

Subjects/Keywords: Solidificação; Microestrutura; Ligas de alumínio; Porosidade; Solidification; Microstructure; Aluminium alloys; Porosity

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gomes, L. G. (2012). Microestrutura dendrítica, macrossegregação e microporosidade na solidificação de ligas ternárias Al-Si-Cu: Dendritic microstructure, macrosegregation and microporosity in the solidification of ternary Al-Si-Cu alloys. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/264725

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gomes, Laercio Gouvea. “Microestrutura dendrítica, macrossegregação e microporosidade na solidificação de ligas ternárias Al-Si-Cu: Dendritic microstructure, macrosegregation and microporosity in the solidification of ternary Al-Si-Cu alloys.” 2012. Thesis, Universidade Estadual de Campinas. Accessed January 23, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264725.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gomes, Laercio Gouvea. “Microestrutura dendrítica, macrossegregação e microporosidade na solidificação de ligas ternárias Al-Si-Cu: Dendritic microstructure, macrosegregation and microporosity in the solidification of ternary Al-Si-Cu alloys.” 2012. Web. 23 Jan 2021.

Vancouver:

Gomes LG. Microestrutura dendrítica, macrossegregação e microporosidade na solidificação de ligas ternárias Al-Si-Cu: Dendritic microstructure, macrosegregation and microporosity in the solidification of ternary Al-Si-Cu alloys. [Internet] [Thesis]. Universidade Estadual de Campinas; 2012. [cited 2021 Jan 23]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/264725.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gomes LG. Microestrutura dendrítica, macrossegregação e microporosidade na solidificação de ligas ternárias Al-Si-Cu: Dendritic microstructure, macrosegregation and microporosity in the solidification of ternary Al-Si-Cu alloys. [Thesis]. Universidade Estadual de Campinas; 2012. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/264725

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade Estadual de Campinas

11. Freitas Feitosa, Emmanuelle Sá, 1980-. Desenvolvimento de correlações entre microestruturas de solidificação e resistências ao desgaste e à corrosão: Development of correlations between solidification microstructures and wear and corrosion resistances.

Degree: 2013, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/264497

► Abstract: Al-based monotectic alloys are particularly important by their tribological characteristics, mainly those having the minority phase (e.g. bismuth, lead and indium) disseminated in particles… (more)

▼ Abstract: Al-based monotectic alloys are particularly important by their tribological characteristics, mainly those having the minority phase (e.g. bismuth, lead and indium) disseminated in particles along the aluminum matrix. These particles have lower melting temperatures and hardness and flow easily due to their inherent self-lubricant properties, leading to good tribological behavior. On the other hand Pb-Sb alloys, even those having low Pb contents, have interesting practical applications. Their intrinsic mechanical and structural characteristics make them appropriate for the manufacture of connectors and positive grids of lead-acid batteries. There is a lack of systematic studies on the microstructural evolution of monotectic alloys under transient solidification conditions associated with application properties. This class of solidification is of prime importance since it encompasses the majority of industrial processes involving the liquid/solid transformation. The present study aims to contribute to the development of correlations between solidification microstructures and wear and corrosion resistances. For this, representative compositions of Al-Pb; Al-Bi e Al-In monotectic alloys have been chosen to permit the effect of microstructural parameters on the wear and corrosion resistances to be analyzed, as well as a hypoeutectic Pb-Sb alloy with a view to evaluating the thermal conditions that are conducive to the development of dendritic tertiary branches and their effect on the corrosion resistance. Directional solidification experiments were carried out under transient conditions to permit the characterization of the thermal evolution and the corresponding as-cast microstructure. The thermal variables, such as the solidification rate and cooling rate have been experimentally determined from the cooling curves acquired along the castings length. Samples of monotectic alloys, having different interphase spacings and diameters of the minority phase, have been subjected to ball crater wear tests, and experimental laws correlating the wear volume with the microstructural interphase spacing are proposed. These samples have also been subjected to corrosion tests in a NaCl solution and correlations between the corrosion resistances and parametric features of the microstructure have also been established. A complementary study on a hypoeutectic Pb-Sb alloy has been developed with a view to identifying the role of tertiary dendritic branches on the corrosion resistances of Pb-Sb alloys. After the microstructural characterization, conditions determining the onset of tertiary dendritic branches have been determined and corrosion tests were carried out on representative samples in a H2SO4 solution. It is also shown how the evolution, the grade and scale of dendritic branches affect the corrosion resistance. The aim of these experimental studies was to establish the pre-programming of solidification conditions in the search of microstructures having higher wear and corrosion resistances Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Garcia, Amauri, 1949- (advisor), Spinelli, Jose Eduardo (coadvisor), Universidade Estadual de Campinas. Faculdade de Engenharia Mecânica (institution), Programa de Pós-Graduação em Engenharia Mecânica (nameofprogram), Mei, Paulo Roberto (committee member), Cheung, Noé (committee member), Neto, Carlos de Moura (committee member), Casteletti, Luiz Carlos (committee member).

Subjects/Keywords: Solidificação; Ligas (Metalurgia); Tribologia; Corrosão; Solidification; Alloys (metallurgy); Tribology; Corrosion

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Freitas Feitosa, Emmanuelle Sá, 1. (2013). Desenvolvimento de correlações entre microestruturas de solidificação e resistências ao desgaste e à corrosão: Development of correlations between solidification microstructures and wear and corrosion resistances. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/264497

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Freitas Feitosa, Emmanuelle Sá, 1980-. “Desenvolvimento de correlações entre microestruturas de solidificação e resistências ao desgaste e à corrosão: Development of correlations between solidification microstructures and wear and corrosion resistances.” 2013. Thesis, Universidade Estadual de Campinas. Accessed January 23, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264497.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Freitas Feitosa, Emmanuelle Sá, 1980-. “Desenvolvimento de correlações entre microestruturas de solidificação e resistências ao desgaste e à corrosão: Development of correlations between solidification microstructures and wear and corrosion resistances.” 2013. Web. 23 Jan 2021.

Vancouver:

Freitas Feitosa, Emmanuelle Sá 1. Desenvolvimento de correlações entre microestruturas de solidificação e resistências ao desgaste e à corrosão: Development of correlations between solidification microstructures and wear and corrosion resistances. [Internet] [Thesis]. Universidade Estadual de Campinas; 2013. [cited 2021 Jan 23]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/264497.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Freitas Feitosa, Emmanuelle Sá 1. Desenvolvimento de correlações entre microestruturas de solidificação e resistências ao desgaste e à corrosão: Development of correlations between solidification microstructures and wear and corrosion resistances. [Thesis]. Universidade Estadual de Campinas; 2013. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/264497

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade Estadual de Campinas

12. Silva, Maria Adrina Paixão de Souza da. Solidificação transitória de ligas dos sistemas monotéticos AI-Bi, AI-Pb e AI-In: Transient solidification of alloys of the monotectic AI-Bi, AI-Pb and AI-In systems.

Degree: 2011, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/265079

► Abstract: Aluminum alloys dispersed with bismuth, lead and indium show promising applications in wearresistant automotive components. Such dispersions of low melting temperature elements decrease hardness… (more)

▼ Abstract: Aluminum alloys dispersed with bismuth, lead and indium show promising applications in wearresistant automotive components. Such dispersions of low melting temperature elements decrease hardness and flow easily under sliding conditions, resulting in favorable tribological behavior. Much research has been devoted in order to better comprehend the distinct morphologies obtained by monotectic reactions. Some researches assume that the interphase spacing evolution in monotectic alloys follows the classical relationship used for eutectics: ?2v = C, or the dendritic growth relationship ?.va.Gb = C, where v is the solidification velocity and C a constant value for both cases, G is the thermal gradient and a and b are constants. Such studies have used Bridgman type het resistance furnaces to produce the directionally solidified monotectic samples. There is a lack of consistent studies on the microstructural development of monotectic alloys during transient heat flowconditions, which are of prime importance since this class of heat flow encompasses the majority of solidification industrial processes. In the present study, directional unsteady-state solidification experiments were carried out with hypomonotectic Al-0.9wt%Pb and Al-5.5wt%In, monotectic Al-1.2wt%Pb and hypermonotectic Al-5.0wt%Bi, Al-7.0wt%Bi and Al-2.1wt%Pb alloys, besides the macrosegregation analysis of the monotectic Al-3.2wt%Bi alloy. Thermal parameters such as the growth rate, cooling rate and thermal gradient were experimentally determined by cooling curves recorded along the casting length. The microstructural evolution was characterized by metallography and the spacings were correlated with the thermal parameters. It is show that the ?2v = C growth law is valid only for the cases where there is a morphology of solute particles irregularly arranged in the matrix and it is not applied on the cases where a cellular monotectic front or fibers and strings of pearls morphologies were observed. On the other hand, ?.va.Gb = C law seems to be able to characterize all the upward cases. The increase in the alloy solute content and induced convective flow affected the morphologies of the resulting phases, the magnitude of the interphase spacing and the diameters of the solute-rich particles Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Garcia, Amauri, 1949- (advisor), Universidade Estadual de Campinas. Faculdade de Engenharia Mecânica (institution), Programa de Pós-Graduação em Engenharia Mecânica (nameofprogram), Ierardi, Maria Clara Filippini (committee member), Freire, Celia Marina de Alvarenga (committee member), Spinelli, Jose Eduardo (committee member), Rocha, Otavio Fernandes Lima da (committee member).

Subjects/Keywords: Solidificação; Microestrutura; Ligas de alumínio; Convecção; Solidification; Microstructure; Aluminium Alloys; Convection

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Silva, M. A. P. d. S. d. (2011). Solidificação transitória de ligas dos sistemas monotéticos AI-Bi, AI-Pb e AI-In: Transient solidification of alloys of the monotectic AI-Bi, AI-Pb and AI-In systems. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/265079

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Silva, Maria Adrina Paixão de Souza da. “Solidificação transitória de ligas dos sistemas monotéticos AI-Bi, AI-Pb e AI-In: Transient solidification of alloys of the monotectic AI-Bi, AI-Pb and AI-In systems.” 2011. Thesis, Universidade Estadual de Campinas. Accessed January 23, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265079.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Silva, Maria Adrina Paixão de Souza da. “Solidificação transitória de ligas dos sistemas monotéticos AI-Bi, AI-Pb e AI-In: Transient solidification of alloys of the monotectic AI-Bi, AI-Pb and AI-In systems.” 2011. Web. 23 Jan 2021.

Vancouver:

Silva MAPdSd. Solidificação transitória de ligas dos sistemas monotéticos AI-Bi, AI-Pb e AI-In: Transient solidification of alloys of the monotectic AI-Bi, AI-Pb and AI-In systems. [Internet] [Thesis]. Universidade Estadual de Campinas; 2011. [cited 2021 Jan 23]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/265079.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Silva MAPdSd. Solidificação transitória de ligas dos sistemas monotéticos AI-Bi, AI-Pb e AI-In: Transient solidification of alloys of the monotectic AI-Bi, AI-Pb and AI-In systems. [Thesis]. Universidade Estadual de Campinas; 2011. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/265079

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

13. Martin, John Hunter. A Methodology and Analysis of Inoculation in Additive Aluminum Alloys.

Degree: 2018, University of California – eScholarship, University of California

URL: http://www.escholarship.org/uc/item/6fg8s2p7

► Metal additive manufacturing, or 3D printing, has the potential to be an incredibly disruptive technology for the fabrication and integration of complex components in a… (more)

▼ Metal additive manufacturing, or 3D printing, has the potential to be an incredibly disruptive technology for the fabrication and integration of complex components in a variety of industries, ranging from automotive and aerospace to medical devices and sporting goods. Until recently, additive manufacturing of metals was mostly used for non-critical or prototyping applications, however a global push for improved energy efficiency via light weighting and topological optimization, as well as reduced cost via lower material waste and near net-shape fabrication, is pushing metal additive manufacturing out of the prototype stage and into full scale production. This has led to a large investment in development of additive metals technologies, however this has mostly been focused on the improvement of additive equipment with a focus on better repeatability, quality, and throughput. There has been relatively little focus on improvements of the materials which are used in additive manufacturing, which have been limited to a few “weldable” alloy systems such as Al10SiMg, Ti6Al4V, and Inconel 718. While these alloy systems have provided a good first step in development of the additive industry, they are extremely limited when compared to the >5000 different alloy compositions available in either cast or wrought forms. This limitation is driven by the unique processing conditions of additive manufacturing which differ significantly from conventional bulk material production developed over centuries, if not millennia. This dissertation investigates the unique solidification conditions present during additive manufacturing of aluminum alloys and attempts to understand how novel inoculant methodologies may be used to not only control microstructure evolution of model unalloyed aluminum systems but extend the available alloy systems beyond what was previously considered amenable to the additive process. The potential scope of additive manufacturing both from a technological and applications space is vast. Therefore, this dissertation is focused on a single additive processing route (laser powder bed fusion) and alloy system (aluminum). Aluminum was chosen after an investigation of available additive alloys indicated that the aluminum alloys, in particular, provided the lowest additive material strength (~200MPa, AlSi10Mg) vs their wrought counterparts (>400 MPa, 7000 Series Al). This is driven by the high crack susceptibility of many high strength aluminum alloys during solidification. It was hypothesized, and has been indicated in the literature, that formation of fine equiaxed microstructures can decrease the susceptibility of these systems to solidification cracking. Until now, microstructure control in additive was limited to parametric manipulation of print parameters, however this has been difficult to broadly implement across all alloy systems. This research leveraged the concept of inoculation to aid in the control of microstructure and improve the processing of additive aluminum alloys. This dissertation has…

Subjects/Keywords: Materials Science; Additive Manufacturing; Aluminum Alloys; Nucleation; Solidification

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APA (6^th Edition):

Martin, J. H. (2018). A Methodology and Analysis of Inoculation in Additive Aluminum Alloys. (Thesis). University of California – eScholarship, University of California. Retrieved from http://www.escholarship.org/uc/item/6fg8s2p7

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Martin, John Hunter. “A Methodology and Analysis of Inoculation in Additive Aluminum Alloys.” 2018. Thesis, University of California – eScholarship, University of California. Accessed January 23, 2021. http://www.escholarship.org/uc/item/6fg8s2p7.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Martin, John Hunter. “A Methodology and Analysis of Inoculation in Additive Aluminum Alloys.” 2018. Web. 23 Jan 2021.

Vancouver:

Martin JH. A Methodology and Analysis of Inoculation in Additive Aluminum Alloys. [Internet] [Thesis]. University of California – eScholarship, University of California; 2018. [cited 2021 Jan 23]. Available from: http://www.escholarship.org/uc/item/6fg8s2p7.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Martin JH. A Methodology and Analysis of Inoculation in Additive Aluminum Alloys. [Thesis]. University of California – eScholarship, University of California; 2018. Available from: http://www.escholarship.org/uc/item/6fg8s2p7

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

14. Symeonidis, Kimon. The Controlled Diffusion Solidification Process: Fundamentals and Principles.

Degree: PhD, 2009, Worcester Polytechnic Institute

URL: etd-042909-102711 ; https://digitalcommons.wpi.edu/etd-dissertations/215

► Aluminum based alloys can be broadly classified into two groups: casting alloys and wrought alloys. Wrought Al-based alloys exhibit superior physical and mechanical properties compared… (more)

Subjects/Keywords: Solidification techniques; Wrought alloys; Casting

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APA (6^th Edition):

Symeonidis, K. (2009). The Controlled Diffusion Solidification Process: Fundamentals and Principles. (Doctoral Dissertation). Worcester Polytechnic Institute. Retrieved from etd-042909-102711 ; https://digitalcommons.wpi.edu/etd-dissertations/215

Chicago Manual of Style (16^th Edition):

Symeonidis, Kimon. “The Controlled Diffusion Solidification Process: Fundamentals and Principles.” 2009. Doctoral Dissertation, Worcester Polytechnic Institute. Accessed January 23, 2021. etd-042909-102711 ; https://digitalcommons.wpi.edu/etd-dissertations/215.

MLA Handbook (7^th Edition):

Symeonidis, Kimon. “The Controlled Diffusion Solidification Process: Fundamentals and Principles.” 2009. Web. 23 Jan 2021.

Vancouver:

Symeonidis K. The Controlled Diffusion Solidification Process: Fundamentals and Principles. [Internet] [Doctoral dissertation]. Worcester Polytechnic Institute; 2009. [cited 2021 Jan 23]. Available from: etd-042909-102711 ; https://digitalcommons.wpi.edu/etd-dissertations/215.

Council of Science Editors:

Symeonidis K. The Controlled Diffusion Solidification Process: Fundamentals and Principles. [Doctoral Dissertation]. Worcester Polytechnic Institute; 2009. Available from: etd-042909-102711 ; https://digitalcommons.wpi.edu/etd-dissertations/215

Universidade Estadual de Campinas

15. Rodrigues, Adilson Vitor, 1988-. Correlações entre microestruturas de solidificação e resistências mecânica e à corrosão de ligas Al-Cu-Ni: Correlations between solidification microstructures and mechanical and corrosion resistances of Al-Cu-Ni alloys.

Degree: 2017, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/330826

► Abstract: Al-Cu-Ni alloys are of scientific and technological interest due to high strength/high temperature applications, based on the reinforcement originated from the interaction between the… (more)

▼ Abstract: Al-Cu-Ni alloys are of scientific and technological interest due to high strength/high temperature applications, based on the reinforcement originated from the interaction between the Al-rich phase and intermetallic composites. The nature, morphology, size, volume fraction and dispersion of IMCs particles throughout the Al-rich matrix are important factors determining the resulting mechanical and chemical properties. The present work aims to evaluate the effect of the addition of 1wt%Ni into Al-5wt%Cu and Al-15wt%Cu alloys on the solidification rate, macrosegregation, microstructure features and the interrelations of such characteristics on tensile and corrosion properties. Therefore, upward transient directional solidification experiments were carried out permitting a wide range of microstructural scales to be examined. Experimental laws relating the evolution of microstructural parameters (primary and secondary dendritic spacings) with solidification thermal parameters (cooling rate - and growth rate - VL) were established. Hall-Petch type experimental laws relating tensile properties with primary dendritic spacing were proposed. Representative samples from the as-cast ingot were submitted to corrosion tests in a 0.06M NaCl solution. The results indicated similar variation of solidification thermal parameters (VL, and thermal gradient - GL) independent of the alloy composition. Although both alloys were characterized essentially by dendritic microstructure along the entire ingots lengths, the Al-15wt%Cu-1wt%Ni alloy showed a more refined microstructure and through a qualitative analysis, higher volumetric fraction of intermetallic composites when compared to the Al-5wt%Cu-1wt%Ni alloy. Higher solidification rates resulted in a non-lamellar eutectic mixture of ?-Al/Al2Cu and coarse Ni-rich IMC while lower cooling rates indicated the formation of the Al7Cu4Ni IMC with Chinese Script morphology. It is shown that the mechanical response of the alloys is directly influenced by both the positive Cu segregation and by the morphologies of the phases. The results of the mechanical tensile tests have evidenced higher values of specific elongation and ultimate tensile strength with the primary dendritic spacing decrease achieving higher values when compared to the hypoeutectic Al-Cu binary alloys available in literature. Considering a compromise between ultimate tensile strength - ?U and corrosion resistance - CR of the alloys samples examined from both alloys castings, it is shown that the samples attaining more refined microstructures are associated with best properties such as ?U achieving values of 180MPa and 318MPa and CR, values of 6,66 cm²/?A and 1,13 cm²/?A respectively for Al-5wt%Cu-1wt%Ni and Al-15wt%Cu-1wt%Ni alloys Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Cheung, Noé, 1974- (advisor), Universidade Estadual de Campinas. Faculdade de Engenharia Mecânica (institution), Programa de Pós-Graduação em Engenharia Mecânica (nameofprogram), Zavaglia, Cecília Amélia de Carvalho (committee member), Ierardi, Maria Clara Filippini (committee member), Sandor, Leonardo Taborda (committee member), Silva, Maurício de Carvalho (committee member).

Subjects/Keywords: Ligas; Solidificação; Microestrutura; Corrosão; Alloys; Solidification; Microstructure; Corrosion

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APA (6^th Edition):

Rodrigues, Adilson Vitor, 1. (2017). Correlações entre microestruturas de solidificação e resistências mecânica e à corrosão de ligas Al-Cu-Ni: Correlations between solidification microstructures and mechanical and corrosion resistances of Al-Cu-Ni alloys. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/330826

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Rodrigues, Adilson Vitor, 1988-. “Correlações entre microestruturas de solidificação e resistências mecânica e à corrosão de ligas Al-Cu-Ni: Correlations between solidification microstructures and mechanical and corrosion resistances of Al-Cu-Ni alloys.” 2017. Thesis, Universidade Estadual de Campinas. Accessed January 23, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/330826.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Rodrigues, Adilson Vitor, 1988-. “Correlações entre microestruturas de solidificação e resistências mecânica e à corrosão de ligas Al-Cu-Ni: Correlations between solidification microstructures and mechanical and corrosion resistances of Al-Cu-Ni alloys.” 2017. Web. 23 Jan 2021.

Vancouver:

Rodrigues, Adilson Vitor 1. Correlações entre microestruturas de solidificação e resistências mecânica e à corrosão de ligas Al-Cu-Ni: Correlations between solidification microstructures and mechanical and corrosion resistances of Al-Cu-Ni alloys. [Internet] [Thesis]. Universidade Estadual de Campinas; 2017. [cited 2021 Jan 23]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/330826.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Rodrigues, Adilson Vitor 1. Correlações entre microestruturas de solidificação e resistências mecânica e à corrosão de ligas Al-Cu-Ni: Correlations between solidification microstructures and mechanical and corrosion resistances of Al-Cu-Ni alloys. [Thesis]. Universidade Estadual de Campinas; 2017. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/330826

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Texas – Austin

16. Lopez, Luis Felipe. Implementation of a high-fidelity axisymmetric model in a Vacuum Arc Remelting process.

Degree: MSin Engineering, Mechanical Engineering, 2011, University of Texas – Austin

URL: http://hdl.handle.net/2152/ETD-UT-2011-05-2770

► Vacuum Arc Remelting (VAR) is a secondary process used for homogenization of high-melting-point and oxygen-sensitive materials such as superalloys and titanium alloys. The VAR process… (more)

▼ Vacuum Arc Remelting (VAR) is a secondary process used for homogenization of high-melting-point and oxygen-sensitive materials such as superalloys and titanium alloys. The VAR process is carried out with the aim of melting a large consumable electrode in such a way that the resulting ingot has improved homogeneity. The Specialty Metals Processing Consortium (SMPC) has spent the past 20 years developing technology to improve control over the final ingot remelting and solidification processes to alleviate conditions that lead to the formation of inclusions and segregation. Channel segregates are concentration defects arising during the solidification of large-diameter solute-rich alloys. As manufacturers for turbine engines and generators call for larger ingots, it becomes more difficult to produce them without these defects. If, however, liquid pool depth can be controlled precisely to stabilize the solidification zone in the ingot, we could, in principle, produce larger ingots that are defect free. A problem arises because measurements obtained from the VAR furnace do not give enough information to accurately estimate the liquid pool shape in dynamic melting situations. Also, the solidification process in VAR is extremely complex due to the multiple physical domains present and a high-fidelity model is required to give an accurate description of the dynamic process. The Basic Axisymmetric Remelting (BAR) code was initially developed by Lee Bertram at Sandia National Laboratories as a high-fidelity multi-energy model to describe ingot casting in this system. In this work we present a new strategy to improve the accuracy of the estimates used in the control system. This strategy consists of implementing BAR as a new set of measurements to be used by the estimator. This new strategy was used in tests jointly sponsored by SMPC and Los Alamos National Laboratory (LANL) in February 2011 using a laboratory-scale furnace and alloy 718 electrodes. Advisors/Committee Members: Beaman, Joseph J. (advisor), Williamson, Rodney L. (committee member).

Subjects/Keywords: Vacuum Arc Remelting; Superalloys; Titanium alloys; Solidification; Channel segregates

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APA (6^th Edition):

Lopez, L. F. (2011). Implementation of a high-fidelity axisymmetric model in a Vacuum Arc Remelting process. (Masters Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/ETD-UT-2011-05-2770

Chicago Manual of Style (16^th Edition):

Lopez, Luis Felipe. “Implementation of a high-fidelity axisymmetric model in a Vacuum Arc Remelting process.” 2011. Masters Thesis, University of Texas – Austin. Accessed January 23, 2021. http://hdl.handle.net/2152/ETD-UT-2011-05-2770.

MLA Handbook (7^th Edition):

Lopez, Luis Felipe. “Implementation of a high-fidelity axisymmetric model in a Vacuum Arc Remelting process.” 2011. Web. 23 Jan 2021.

Vancouver:

Lopez LF. Implementation of a high-fidelity axisymmetric model in a Vacuum Arc Remelting process. [Internet] [Masters thesis]. University of Texas – Austin; 2011. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/2152/ETD-UT-2011-05-2770.

Council of Science Editors:

Lopez LF. Implementation of a high-fidelity axisymmetric model in a Vacuum Arc Remelting process. [Masters Thesis]. University of Texas – Austin; 2011. Available from: http://hdl.handle.net/2152/ETD-UT-2011-05-2770

Colorado School of Mines

17. Watson, Jonathan S. Fiber laser weldability of austenitic nickel alloys.

Degree: MS(M.S.), Metallurgical and Materials Engineering, 2017, Colorado School of Mines

URL: http://hdl.handle.net/11124/171828

► Recent developments of fiber lasers allow for easier beam delivery facilitating greater applications for laser welding in industry. Welding with high energy density heat sources… (more)

▼ Recent developments of fiber lasers allow for easier beam delivery facilitating greater applications for laser welding in industry. Welding with high energy density heat sources allows for faster travel speeds, faster cooling rates, and smaller heat affected zones. However, there is a still a lack of knowledge base on how laser welding process parameters affect the weldability of austenitic nickel alloys. In this work, laser welds were made on several austenitic nickel alloys from different alloy families: HAYNES® 214® alloy, HAYNES® 282® alloy, HAYNES® 230® alloy, HAYNES® HR-120® alloy, HAYNES® HR-160® alloy, HAYNES® 188 alloy, HAYNES® 718 alloy. Welds were made at 25 mm/s at laser powers ranging from 400 to 600 Watts. Solidification cracking was observed in cross-sections of the fusion zone of HR-160® alloy and HR-120® alloy. Dendritic solidification was found in all alloys, and partitioning within the dendritic structure compared well with Scheil calculations performed using ThermoCalc software. A eutectic liquid rich in carbide forming elements was found at the interdendritic regions in 188, 230®, 282®, and 718 alloys and was quantified by processing backscatter electron images of the fusion zone. This interdendritic liquid was found to back fill solidification cracks that formed in the fusion zone during weldability testing. Transverse Varestraint and Sigma-Jig testing were performed to rank the weldability of alloys. During Transvarestraint testing, the ram drop timing was recorded in relation to the laser output, and a type R thermocouple was also placed in the laser path, and the approximate cooling rate of the fusion zone was recorded and used to calculate the solidification cracking temperature range. Rankings of the weldability compared well between Sigma-Jig and Transvarestraint testing, with the exception of 214 alloy and HR-120 alloy, which ranked much better and worse, respectively in Sigma-Jig tests. A possible explanation for this difference is the higher thermal conductivity and lower yields strength of 214 alloy and high temperatures, allowing it to accommodate more stress in the Sigma-Jig test. The final ranking of alloys from more weldable to less weldable by Sigma-Jig testing is 188, 214, 282, 718, 230, HR-120, and HR-160. The final ranking by maximum crack length in Transvarestraint specimens listed from more weldable to less weldable is: 188, 282, HR-120, 718, 230, 214, and HR-160. Advisors/Committee Members: Liu, Stephen (advisor), Sowards, Jeffrey (advisor), Caron, Jeremy (committee member), Pfeif, Erik (committee member), Yu, Zhenzhen (committee member).

Subjects/Keywords: nickel alloys; solidification cracking; weldability; Sigma-Jig; laser welding; transvarestraint

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APA (6^th Edition):

Watson, J. S. (2017). Fiber laser weldability of austenitic nickel alloys. (Masters Thesis). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/171828

Chicago Manual of Style (16^th Edition):

Watson, Jonathan S. “Fiber laser weldability of austenitic nickel alloys.” 2017. Masters Thesis, Colorado School of Mines. Accessed January 23, 2021. http://hdl.handle.net/11124/171828.

MLA Handbook (7^th Edition):

Watson, Jonathan S. “Fiber laser weldability of austenitic nickel alloys.” 2017. Web. 23 Jan 2021.

Vancouver:

Watson JS. Fiber laser weldability of austenitic nickel alloys. [Internet] [Masters thesis]. Colorado School of Mines; 2017. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/11124/171828.

Council of Science Editors:

Watson JS. Fiber laser weldability of austenitic nickel alloys. [Masters Thesis]. Colorado School of Mines; 2017. Available from: http://hdl.handle.net/11124/171828

Colorado School of Mines

18. Nelson, Scott David. Multiphase wide gap braze alloys for the repair of nickel-base superalloy turbine components: development and characterization.

Degree: MS(M.S.), Metallurgical and Materials Engineering, 2013, Colorado School of Mines

URL: http://hdl.handle.net/11124/79355

► Gas turbine components made of nickel-base superalloys experience cracking after service in extreme environments. As these cracks can be wide, brazing or fusion welding is… (more)

▼ Gas turbine components made of nickel-base superalloys experience cracking after service in extreme environments. As these cracks can be wide, brazing or fusion welding is typically used to repair them. Properly designed and applied, brazing filler metal will help extend the useful life of damaged turbine components. During repair of defective OEM parts, brazing is also considered, provided that proper filler metals with enhanced ductility and improved resistance to low-cycle fatigue are available. This research strives to develop the brazing technique and alloys to achieve a repair with acceptable mechanical properties. Additionally, the effects of silicon and boron, as fast diffusing and melting point suppressing elements on the braze microstructure and mechanical properties were examined in detail to help guide future alloy development. Three commercially available "low-temperature" brazing powders were mixed with an additive superalloy powder to prepare a series of filler metals for wide gap brazing used to repair OEM gas turbine components. BNi-2 (Ni-7Cr-4.2Si-3B-3Fe), BNi-5 (Ni-19Cr-10Si) and BNi-9 (Ni-15Cr-3.5B) were mixed with MARM247 (Ni-10W-10Co-8.25Cr-5.5Al-3Ta-1Ti-0.7Mo- 0.5Fe-0.015B) at ratios of 40, 50, and 60 wt. pct. creating a total of nine experimental filler alloys. The brazes were applied to a 0.06 inch gap in a René 108TM substrate for mechanical and microstructural analysis. The wettability and flow of each of the experimental alloys were analyzed to determine the required brazing temperature through isothermal spreadability experiments. Bend testing was performed on brazed joints to determine their mechanical properties and maximum angular deflection. The metallurgical driving factors, such as solidification behavior and compositional effects, were analyzed to correlate the resulting microstructural constituents to the mechanical properties developed through experimentation. It was found that because of the solid solubility of silicon into nickel, greater amounts of single-phase nickel formed surrounding the additive superalloy powder in the brazes containing silicon when compared with brazes without. This effect is advantageous, as it was found that the increase in the additive powder interaction zones resulted in a beneficial increase in mechanical properties, such as strength and percent strain at failure. Alloys containing boron required a lower processing temperature than alloys containing silicon and are good candidates for use in the process if enough time is given for the boron to diffuse into the parent material and therefore encouraging isothermal solidification, disallowing the formation of mechanically detrimental ternary eutectic boride phases. The BNi-2 alloy, containing both boron and silicon, exhibited the beneficial behaviors of heightened interaction between the liquid braze alloy and the additive powder, in addition to the decreased brazing temperature required. Advisors/Committee Members: Liu, Stephen (advisor), Madeni, Juan Carlos (committee member), Kottilingam, Srikanth (committee member), Olson, D. L. (David LeRoy) (committee member).

Subjects/Keywords: wide gap braze; superalloys; mechanical testing; solidification; nickel; Brazing; Brazing alloys; Nickel alloys; Heat resistant alloys; Turbines – Parts

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APA (6^th Edition):

Nelson, S. D. (2013). Multiphase wide gap braze alloys for the repair of nickel-base superalloy turbine components: development and characterization. (Masters Thesis). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/79355

Chicago Manual of Style (16^th Edition):

Nelson, Scott David. “Multiphase wide gap braze alloys for the repair of nickel-base superalloy turbine components: development and characterization.” 2013. Masters Thesis, Colorado School of Mines. Accessed January 23, 2021. http://hdl.handle.net/11124/79355.

MLA Handbook (7^th Edition):

Nelson, Scott David. “Multiphase wide gap braze alloys for the repair of nickel-base superalloy turbine components: development and characterization.” 2013. Web. 23 Jan 2021.

Vancouver:

Nelson SD. Multiphase wide gap braze alloys for the repair of nickel-base superalloy turbine components: development and characterization. [Internet] [Masters thesis]. Colorado School of Mines; 2013. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/11124/79355.

Council of Science Editors:

Nelson SD. Multiphase wide gap braze alloys for the repair of nickel-base superalloy turbine components: development and characterization. [Masters Thesis]. Colorado School of Mines; 2013. Available from: http://hdl.handle.net/11124/79355

Indian Institute of Science

19. Karagadde, Shyamprasad. Multi-Phase Modeling Of Microporosity And Microstructures During Solidification Of Aluminum Alloys.

Degree: PhD, Faculty of Engineering, 2014, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/2303

► Manufacturing of light-weight materials is associated with several types of casting defects during solidification. Porosity defects are common, especially in aluminum and its alloys, which… (more)

▼ Manufacturing of light-weight materials is associated with several types of casting defects during solidification. Porosity defects are common, especially in aluminum and its alloys, which initiate crack propagation and thereby cause drastic deterioration in the mechanical properties. These defects, classified as micro and macro defects (based on their sizes), are mainly governed by release of hydrogen into the liquid at the solid-liquid interface, which triggers the nucleation and growth of hydrogen bubbles in the melt. Subsequently, these bubbles interact with solidifying interfaces such as dendritic arms and eutectic fronts, leading to the formation of pores. Macroscopic defects in the form of voids are created due to solidification shrinkage. The primary focus of the present work is to develop phenomenological models for the evolution of microporosity and microstructures during solidification. The issues outlined above typically occur in multi-phase environments comprising of solid, liquid and gaseous phases, and over a range of length and time scales. Any phenomenological prediction would, therefore, require a multi-phase-scale approach. Principles of volume averaging are applied to equations of conservation to obtain single-field formulations. These are then solved with appropriate interface tracking techniques such as Enthalpy, Level-set, Volume-of-fluid and Immersed-boundary methods. The framework is built up on a standard pressure based incompressible fluid flow solver (SIMPLER algorithm) and coupled modeling strategies are proposed to address the interfacial dynamics. A two-dimensional framework is considered with a fixed-grid Cartesian co-ordinate system. Scaling analyses are performed to bring out the relative effects of various competing parameters in order to obtain further insights into this complex phenomenon. The numerical results and scaling predictions are validated against experimental observations published in literature. In literature, numerical predictions of microporosity mainly include criteria based models based on empirical relations and deterministic/stochastic models based on diffusion driven growth assuming spherical bubbles. The dynamic evolution of non-spherical bubble-metal interface in a three-phase system is yet to be captured. Moreover, several in-situ experiments have shown elongated bubble shapes during the engulfment phase, therefore a criterion to define the dependence on cooling rates and the resulting bubble morphology can possibly deliver further practical insights. We propose a numerical model for hydrogen bubble growth, its movement and subsequent engulfment by a solidifying front, combining the features of level-set and enthalpy methods for tracking bubble-metal and solid-liquid interfaces, respectively. The influx of hydrogen into heterogeneously nucleated bubbles results in growth of bubbles to sizes up to a few hundreds of microns. In the first part of this numerical study, a methodology based on the level-set approach is developed to simultaneously capture… Advisors/Committee Members: Dutta, Pradip (advisor).

Subjects/Keywords: Aluminum Alloys; Microporosity; Microstructures; Aluminum Alloys - Solidification; Multiphase Modeling; Equiaxed Dendrites; Metals - Solidification; Hydrogen Microporosity; Aluminum Alloys - Hydrogen Content; Aluminum Castings; Hydrogen Bubbles; Metallurgy

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APA (6^th Edition):

Karagadde, S. (2014). Multi-Phase Modeling Of Microporosity And Microstructures During Solidification Of Aluminum Alloys. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2303

Chicago Manual of Style (16^th Edition):

Karagadde, Shyamprasad. “Multi-Phase Modeling Of Microporosity And Microstructures During Solidification Of Aluminum Alloys.” 2014. Doctoral Dissertation, Indian Institute of Science. Accessed January 23, 2021. http://etd.iisc.ac.in/handle/2005/2303.

MLA Handbook (7^th Edition):

Karagadde, Shyamprasad. “Multi-Phase Modeling Of Microporosity And Microstructures During Solidification Of Aluminum Alloys.” 2014. Web. 23 Jan 2021.

Vancouver:

Karagadde S. Multi-Phase Modeling Of Microporosity And Microstructures During Solidification Of Aluminum Alloys. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2014. [cited 2021 Jan 23]. Available from: http://etd.iisc.ac.in/handle/2005/2303.

Council of Science Editors:

Karagadde S. Multi-Phase Modeling Of Microporosity And Microstructures During Solidification Of Aluminum Alloys. [Doctoral Dissertation]. Indian Institute of Science; 2014. Available from: http://etd.iisc.ac.in/handle/2005/2303

Ryerson University

20. Elsayed, Abdallah. Inclusion removal and grain refinement of magnesium alloy castings.

Degree: 2015, Ryerson University

URL: https://digital.library.ryerson.ca/islandora/object/RULA%3A4685

► Magnesium alloys show promise to be materials for lightweighting of automotive and aerospace vehicles improving fuel efficiencies and vehicle performance. A majority of magnesium alloy… (more)

▼ Magnesium alloys show promise to be materials for lightweighting of automotive and aerospace vehicles improving fuel efficiencies and vehicle performance. A majority of magnesium alloy components are produced using casting where susceptibility to forming inclusions and coarse grain sizes could result. Development of effective inclusion removal techniques and better understanding of grain refinement of magnesium alloys could help in improving their mechanical properties to advance them to more structurally demanding applications. This research aimed to develop an environmentally friendly alternative to the grain refinement and inclusion removal capabilities of carbon based hexachloroethane as it releases dioxins, chlorine gas and corrodes foundry equipment. A secondary aim was to pioneer in-situ neutron diffraction to examine the solidification of magnesium alloys. The research involved preparing tensile samples of AZ91E magnesium alloy using permanent mould casting. Inclusion removal was conducted by using filtration and argon gas bubbling. Castings grain refined using hexachloroethane (0.25, 0.50 and 0.75 wt.%) were compared against ex-situ aluminum-silicon carbide and in-situ aluminum-carbon based grain refiners combined with filtration and argon gas bubbling. Further, in-situ neutron diffraction was utilized for phase analysis and fraction solid determination of magnesium-zinc and magnesium-aluminum alloys. There was a significant improvement in yield strength, ultimate tensile strength and elongation with filtration plus argon bubbling, carbon inoculation or both filtration plus argon bubbling and carbon inoculation. The results indicated that the mechanism of the observed ~20% reduction in grain sizes with carbon inoculation (hexachloroethane, ex-situ aluminum-silicon carbide and in-situ aluminum-carbon) was explained through duplex nucleation of Mn-Al and Al-Mg-C-O (likely Al2MgC2) phases. Finally, in-situ neutron diffraction was used to follow the formation of Mg17Al12 eutectic phase in a magnesium-9 wt.% aluminum alloy. For the magnesium-zinc alloys, in-situ neutron diffraction enabled characterization of the effects of zirconium to the fraction solid growth of (1010), (0002) and (1011) α-Mg planes. The societal and environmental impact of this research is significant. There is a clear demonstration of alternatives to the universally used hexachloroethane grain refiner promoting harmful emissions. Improved mechanical properties resulting from new grain refinement and iv inclusion filtration are a major advancement in promoting weight reduction, improved castability and decreased environmental impact for automotive and aerospace industries.

Subjects/Keywords: Metals, inclusions; Magnesium alloys; Strength of materials – Mathematical models; Metal castings – Mechanical properties; Solidification; Metals – Rapid solidification processing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Elsayed, A. (2015). Inclusion removal and grain refinement of magnesium alloy castings. (Thesis). Ryerson University. Retrieved from https://digital.library.ryerson.ca/islandora/object/RULA%3A4685

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Elsayed, Abdallah. “Inclusion removal and grain refinement of magnesium alloy castings.” 2015. Thesis, Ryerson University. Accessed January 23, 2021. https://digital.library.ryerson.ca/islandora/object/RULA%3A4685.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Elsayed, Abdallah. “Inclusion removal and grain refinement of magnesium alloy castings.” 2015. Web. 23 Jan 2021.

Vancouver:

Elsayed A. Inclusion removal and grain refinement of magnesium alloy castings. [Internet] [Thesis]. Ryerson University; 2015. [cited 2021 Jan 23]. Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A4685.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Elsayed A. Inclusion removal and grain refinement of magnesium alloy castings. [Thesis]. Ryerson University; 2015. Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A4685

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université de Grenoble

21. Bouffier, Lionel. Modélisation de la fissuration à chaud lors du soudage de l'alliage base nickel IN600 : Modeling of hot cracking during welding of Nickel base IN600.

Degree: Docteur es, Matériaux, mécanique, génie civil, électrochimie, 2013, Université de Grenoble

URL: http://www.theses.fr/2013GRENI073

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La fissuration à chaud de solidification qui est l'un des problèmes majeurs rencontrés dans le cadre du soudage pourrait être préjudiciable à la tenue en… (more)

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La fissuration à chaud de solidification qui est l'un des problèmes majeurs rencontrés dans le cadre du soudage pourrait être préjudiciable à la tenue en service de structures mécano-soudées. Ce phénomène correspond à la formation de fissures en fin de solidification sous l'effet des déformations induites par les contraintes thermiques et le retrait de solidification. Ces travaux de thèse portent sur la modélisation de la fissuration à chaud dans un alliage base nickel en soudage TIG. L'objectif est de proposer une méthodologie permettant d'estimer le risque de fissuration dans l'Inconel 600. Pour cela des essais de soudage instrumentés en température ont été développés de manière à déterminer les conditions d'apparition et de propagation du défaut. Ces essais ont ensuite été modélisés dans l'optique d'établir un critère de fissuration fondé sur la déformation de l'alliage en fin de solidification, déformation qui ne peut être mesurée expérimentalement. La principale valeur ajoutée de cette étude réside dans le fait que le comportement viscoplastique du matériau utilisé lors de la modélisation a été déterminé expérimentalement de la température ambiante à la zone de transition pâteuse au moyen d'essais de caractérisation mécanique spécifiques. Les essais réalisés à l'état semi-solide pour des températures avoisinant 1400 °C ont notamment alimenté un modèle de zone cohésive permettant de modéliser la propagation des fissures. Cette approche couplant expériences et modélisation a ainsi conduit à l'identification d'un critère de fissuration à chaud intrinsèque à l'Inconel 600.

Hot cracking which is one of the major problems in welding may be prejudicial to the safety of welded structures. This phenomenon corresponds to the formation of irreversible cracks at the end of solidification, due to tensile strains associated with solidification shrinkage and thermal contraction. This work focuses on the hot cracking modeling during the welding of a Nickel based alloy. The aim is to propose a methodology which allows estimating the hot cracking risk in the Inconel 600 alloy. To achieve that purpose, self-restrained welding tests with temperature measurements have been developed in order to identify the conditions leading to the defect formation and propagation. These tests have then been modeled to establish a hot cracking criterion based on the strain applied on the alloy at the end of solidification, strain which cannot be experimentally measured. The originality of this study consists in the fact that the viscoplastic behaviour of the studied material (used for thermomechanical modeling) has been determined experimentally from room temperature up to the mushy zone using specific set-ups. Mechanical characterization tests performed in the semi-solid state at temperatures approaching 1400 °C also allowed feeding a cohesive element model leading to crack propagation modeling. This approach coupling experiments with modeling thus led to the identification of a hot cracking criterion intrinsic to Inconel 600.

Advisors/Committee Members: Bréchet, Yves (thesis director), Suéry, Michel (thesis director).

Subjects/Keywords: Modélisation; Soudage; Alliages base nickel; Solidification; Fissuration; Aciers austénitiques; Simulation; Welding; Solidification; Nickel alloys; Cracks; Steel; 620

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bouffier, L. (2013). Modélisation de la fissuration à chaud lors du soudage de l'alliage base nickel IN600 : Modeling of hot cracking during welding of Nickel base IN600. (Doctoral Dissertation). Université de Grenoble. Retrieved from http://www.theses.fr/2013GRENI073

Chicago Manual of Style (16^th Edition):

Bouffier, Lionel. “Modélisation de la fissuration à chaud lors du soudage de l'alliage base nickel IN600 : Modeling of hot cracking during welding of Nickel base IN600.” 2013. Doctoral Dissertation, Université de Grenoble. Accessed January 23, 2021. http://www.theses.fr/2013GRENI073.

MLA Handbook (7^th Edition):

Bouffier, Lionel. “Modélisation de la fissuration à chaud lors du soudage de l'alliage base nickel IN600 : Modeling of hot cracking during welding of Nickel base IN600.” 2013. Web. 23 Jan 2021.

Vancouver:

Bouffier L. Modélisation de la fissuration à chaud lors du soudage de l'alliage base nickel IN600 : Modeling of hot cracking during welding of Nickel base IN600. [Internet] [Doctoral dissertation]. Université de Grenoble; 2013. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2013GRENI073.

Council of Science Editors:

Bouffier L. Modélisation de la fissuration à chaud lors du soudage de l'alliage base nickel IN600 : Modeling of hot cracking during welding of Nickel base IN600. [Doctoral Dissertation]. Université de Grenoble; 2013. Available from: http://www.theses.fr/2013GRENI073

INP Toulouse

22. Ferdian, Deni. Effet de la vitesse de refroidissement sur la taille des grains, la modification eutectique et la précipitation d’intermétalliques riches en fer dans des alliages Al-Si hypoeutectiques : Cooling rate effects on grain size, eutectic modification and Fe-bearing intermetallic precipitation in hypoeutectic Al-Si alloys.

Degree: Docteur es, Science et Génie des Matériaux, 2014, INP Toulouse

URL: http://www.theses.fr/2014INPT0046

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Les alliages aluminium-silicium sont les alliages d’aluminium de moulage les plus couramment employés en raison de leur faible poids, de leurs caractéristiques mécaniques et de… (more)

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Les alliages aluminium-silicium sont les alliages d’aluminium de moulage les plus couramment employés en raison de leur faible poids, de leurs caractéristiques mécaniques et de leur fluidité. Leurs propriétés mécaniques, en particulier leur résistance, peuvent être améliorées par l’affinage des grains et la modification des précipités de silicium. Par contre, la précipitation de composés intermétalliques riches en fer, comme la phase dite beta, a un effet néfaste sur la tenue en traction et la ductilité de ces alliages. Bien que diverses méthodes aient été proposées pour atténuer les effets de la phase beta, la compréhension des mécanismes de sa croissance pourrait s’avérer utile pour réduire ses effets néfastes. L’objectif de cette étude est d’établir la relation entre la vitesse de refroidissement et les caractéristiques microstructurales des alliages Al-Si hypoeutectiques. Dans une pièce coulée réelle, la vitesse de refroidissement locale peut grandement changer d’un point à l’autre du fait de la géométrie de la pièce mais aussi du fait des paramètres de coulée. Les variations de vitesse de refroidissement affectent le processus de solidification, et ceci est rendu évident par les changements des températures caractéristiques des courbes de refroidissement enregistrées en différents endroits d’une pièce. Les relations entre ces températures caractéristiques et la taille des grains et la modification du silicium eutectique sont présentées. Cette étude a aussi porté sur l’effet de la vitesse de refroidissement sur la morphologie de la phase beta dans le cas d’un alliage ternaire Al-Fe-Si. La croissance de la phase beta a été caractérisée par tomographie post-mortem et in-situ. Enfin, certains écarts par rapport aux caractéristiques de solidification usuelles, telles que la précipitation en écriture chinoise de la phase beta et la formation de rosettes, ont été observés et sont discutés.

Aluminum-silicon alloys are the most common aluminum casting alloys produced due to their fluidity characteristic and mechanical and light weight properties. However, there are several issues concerning application of Al-Si hypoeutectic alloys such as strength, which may be improved by refining grain size of the alloy and modifying silicon precipitates. Furthermore, precipitation of Fe-bearing intermetallics such as the so-called beta phase has a detrimental effect on tensile and ductility properties of Al-Si hypoeutectic alloys. Although various methods have been proposed to mitigate the effect of beta phase, the understanding of the mechanism of growth may be useful to reduce its detrimental effects. The objective of this study is to establish the relationship between the cooling rate and morphology features in Al-Si hypoeutectic alloys. In real casting condition, cooling rate is one of the factors that is not easy to predict, because it is related to the geometry of the parts and to the casting process itself. Changes in cooling rate affect the solidification process, and this is made apparent by the changes in the…

Advisors/Committee Members: Lacaze, Jacques (thesis director).

Subjects/Keywords: Al-Si alliages; Intermétalliques; Vitesse de refroidissement; Tomographie; Solidification; Moulage; Al-Si alloys; Intermetallics; Cooling rate; Tomography; Solidification; Casting

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ferdian, D. (2014). Effet de la vitesse de refroidissement sur la taille des grains, la modification eutectique et la précipitation d’intermétalliques riches en fer dans des alliages Al-Si hypoeutectiques : Cooling rate effects on grain size, eutectic modification and Fe-bearing intermetallic precipitation in hypoeutectic Al-Si alloys. (Doctoral Dissertation). INP Toulouse. Retrieved from http://www.theses.fr/2014INPT0046

Chicago Manual of Style (16^th Edition):

Ferdian, Deni. “Effet de la vitesse de refroidissement sur la taille des grains, la modification eutectique et la précipitation d’intermétalliques riches en fer dans des alliages Al-Si hypoeutectiques : Cooling rate effects on grain size, eutectic modification and Fe-bearing intermetallic precipitation in hypoeutectic Al-Si alloys.” 2014. Doctoral Dissertation, INP Toulouse. Accessed January 23, 2021. http://www.theses.fr/2014INPT0046.

MLA Handbook (7^th Edition):

Ferdian, Deni. “Effet de la vitesse de refroidissement sur la taille des grains, la modification eutectique et la précipitation d’intermétalliques riches en fer dans des alliages Al-Si hypoeutectiques : Cooling rate effects on grain size, eutectic modification and Fe-bearing intermetallic precipitation in hypoeutectic Al-Si alloys.” 2014. Web. 23 Jan 2021.

Vancouver:

Ferdian D. Effet de la vitesse de refroidissement sur la taille des grains, la modification eutectique et la précipitation d’intermétalliques riches en fer dans des alliages Al-Si hypoeutectiques : Cooling rate effects on grain size, eutectic modification and Fe-bearing intermetallic precipitation in hypoeutectic Al-Si alloys. [Internet] [Doctoral dissertation]. INP Toulouse; 2014. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2014INPT0046.

Council of Science Editors:

Ferdian D. Effet de la vitesse de refroidissement sur la taille des grains, la modification eutectique et la précipitation d’intermétalliques riches en fer dans des alliages Al-Si hypoeutectiques : Cooling rate effects on grain size, eutectic modification and Fe-bearing intermetallic precipitation in hypoeutectic Al-Si alloys. [Doctoral Dissertation]. INP Toulouse; 2014. Available from: http://www.theses.fr/2014INPT0046

Université de Lorraine

23. Cisternas Fernández, Martín Matías. Modeling of solidification of TiAl alloys in centrifugal casting : Modélisation de la solidification des alliages TiAl en coulée centrifuge.

Degree: Docteur es, Sciences des matériaux, 2019, Université de Lorraine

URL: http://www.theses.fr/2019LORR0218

►

Les alliages TiAl sont un groupe de matériaux important pour les industries automobile et aérospatiale, de par leur faible densité et bonne tenue mécanique à… (more)

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Les alliages TiAl sont un groupe de matériaux important pour les industries automobile et aérospatiale, de par leur faible densité et bonne tenue mécanique à haute température. Cependant, à cause de leur forte réactivité à l’état liquide, au moment de couler ces alliages, il faut utiliser une faible surchauffe pour limiter la contamination. La coulée centrifuge est une option pour améliorer le remplissage du moule à faible surchauffe. En coulée centrifuge, l’effet de la poussée d’Archimède sur le mouvement du liquide est renforcé, ce qui modifie l’écoulement par l’effet combiné de la force centrifuge et de force de Coriolis qui apparaissent dans le système en rotation. Ceci fait que des motifs particuliers de macroségrégation et de distribution de microstructures se forment dans la pièce solidifiée, et l’origine de ces motifs n’est pas très bien comprise. L’objectif de cette thèse est d’expliquer l’écoulement du liquide ainsi que le transport des grains solides et des espèces chimiques pendant la solidification d’alliages TiAl en coulée centrifuge. Un modèle 3D volume finis de solidification multi-échelle a d’abord été développé dans le cadre de cette thèse. Un tel modèle était nécessaire à cause de la nature tridimensionnelle des écoulements. Le modèle a ensuite été utilisé pour simuler des essais expérimentaux de solidification dirigée d’échantillons cylindriques en alliage TiAl GE (Ti-47Al-2Cr-2Nb), précédemment réalisés dans le cadre du projet ESA GRADECET. Ces essais ont été réalisés dans la “Large Diameter Centrifuge” de l’ESA, à des intensités de centrifugation entre 5g et 20g, où g est l’accélération standard de la gravité terrestre. Les résultats des simulations montrent que la force de Coriolis modifie complètement l’écoulement du liquide pendant la solidification, résultant en une unique boucle de convection dans le bain liquide. Inversement, la force de Coriolis n’a qu’un faible effet sur le mouvement des grains équiaxes. A forte centrifugation, le mouvement des grains est surtout gouverné par l’équilibre entre la gravité apparente et la force de trainée. Les résultats montrent aussi que la macroségrégation finale de l’aluminium n’est pas symétrique et présente un fort enrichissement le long du bord d’attaque de l’échantillon. Ceci est dû à l’asymétrie de l’écoulement induite par la force de Coriolis.

TiAl alloys are an important material for automotive and aerospace industries due to their low density and high strength at high temperatures. However, due to their high reactivity in liquid state, low superheat must be used in casting in order to limit contamination. Centrifugal casting is an option to enhance mold filling at low superheat. In centrifugal casting the buoyancy driven flow is intensified and the flow structure is modified by the combined effect of the non-inertial accelerations – centrifugal and Coriolis – which appear in the rotating system. The consequence are particular patterns of macrosegregation and of distribution of microstructures in the solidified part. These patterns are not…

Advisors/Committee Members: Combeau, Hervé (thesis director), Založnik, Miha (thesis director).

Subjects/Keywords: Solidification; Coulée centrifuge; Alliage TiAl; Modélisation numérique; Solidification; Centrifugal casting; TiAl alloys; Numerical modeling; 620.16; 671.2

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Cisternas Fernández, M. M. (2019). Modeling of solidification of TiAl alloys in centrifugal casting : Modélisation de la solidification des alliages TiAl en coulée centrifuge. (Doctoral Dissertation). Université de Lorraine. Retrieved from http://www.theses.fr/2019LORR0218

Chicago Manual of Style (16^th Edition):

Cisternas Fernández, Martín Matías. “Modeling of solidification of TiAl alloys in centrifugal casting : Modélisation de la solidification des alliages TiAl en coulée centrifuge.” 2019. Doctoral Dissertation, Université de Lorraine. Accessed January 23, 2021. http://www.theses.fr/2019LORR0218.

MLA Handbook (7^th Edition):

Cisternas Fernández, Martín Matías. “Modeling of solidification of TiAl alloys in centrifugal casting : Modélisation de la solidification des alliages TiAl en coulée centrifuge.” 2019. Web. 23 Jan 2021.

Vancouver:

Cisternas Fernández MM. Modeling of solidification of TiAl alloys in centrifugal casting : Modélisation de la solidification des alliages TiAl en coulée centrifuge. [Internet] [Doctoral dissertation]. Université de Lorraine; 2019. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2019LORR0218.

Council of Science Editors:

Cisternas Fernández MM. Modeling of solidification of TiAl alloys in centrifugal casting : Modélisation de la solidification des alliages TiAl en coulée centrifuge. [Doctoral Dissertation]. Université de Lorraine; 2019. Available from: http://www.theses.fr/2019LORR0218

24. Thielleux, Delphine. Choix des Matériaux et des procédés de mise en forme pour l’allègement des boîtiers d’électronique de puissance des véhicules électriques : Materials selection and manufacturing process development for power electronic control casing of electric vehicles.

Degree: Docteur es, Sciences et génie des matériaux, 2014, Paris, ENMP

URL: http://www.theses.fr/2014ENMP0094

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Pour rendre les véhicules électriques plus attractifs, les recherches actuelles se portent sur l'augmentation de l'autonomie de la batterie. Deux méthodes existent pour le réaliser… (more)

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Pour rendre les véhicules électriques plus attractifs, les recherches actuelles se portent sur l'augmentation de l'autonomie de la batterie. Deux méthodes existent pour le réaliser : travailler sur les technologies de batterie ou alléger le véhicule. Une voie classique d'allègement est de remplacer les matériaux des pièces existantes par d'autres matériaux plus légers. Dans le cas des alliages d'aluminium, les matériaux de remplacement possibles sont les polymères ou les alliages de magnésium. Dans cette étude, l'alliage de magnésium commercial AZ91 a été modifié par ajout d'éléments d'alliages supplémentaires. Des échantillons d'alliages modifiés coulés sable ont été étudiés pour en comparer la microstructure et les comportements mécaniques et face à la corrosion. Des observations de coupes métallographiques avec analyse quantitative d'image ont été couplées avec de la microanalyse X , de la diffraction des rayons X et avec de l'analyse thermique , pour analyser les changements de microstructure et de séquence de précipitation dues aux ajouts. La réponse aux traitements thermiques a aussi été quantifiée. Des essais mécaniques ont été réalisés pour classer les différents alliages de magnésium selon leurs performances. Enfin, l'AZ91D est connu pour son bon comportement en corrosion par rapport aux autres alliages de magnésium. L'influence des ajouts d'éléments sur la performance en corrosion a également été étudiée par des méthodes conventionnelles d'électrochimie et par des essais industriels.

To make electric vehicles more attractive, researches to increase the autonomy of electric vehicles are underway on the battery technology and on the lightening of many vehicle parts. For the second approach, one way is to replace aluminum by magnesium without loosing mechanical and corrosion resistance performance. The AZ91 commercial alloy was modified with additional elements to meet the mechanical requirements for the power electronic casings. Sand casting samples were studied for the comparison of microstructure and properties. First, metallographic observations were performed with an optical microscope and a SEM combined with microanalysis (epma) coupled with quantitative image analysis, then the solidification sequence was analysed using thermal analysis in order to identify the changes in microstructure when alloying. Combined with DTA, X-ray diffraction and micro probe analysis, these techniques are useful to understand the solidification sequence of the complex alloys and their response to heat treatments. Tensile and hardness tests were then performed in order to quantify the mechanical strength of the different samples. Fractographic observations were also done to characterize the rupture of the specimens. AZ91D is known for its good corrosion resistance. Corrosion behaviour of modified alloys was assessed by electrochemical and non-electrochemical methods.

Advisors/Committee Members: Bienvenu, Yves (thesis director).

Subjects/Keywords: Choix de matériaux; Alliages légers; Solidification; Mécanique; Corrosion; Materials selection; Light alloys; Solidification; Mechanical properties; Corrosion; 620.11

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Thielleux, D. (2014). Choix des Matériaux et des procédés de mise en forme pour l’allègement des boîtiers d’électronique de puissance des véhicules électriques : Materials selection and manufacturing process development for power electronic control casing of electric vehicles. (Doctoral Dissertation). Paris, ENMP. Retrieved from http://www.theses.fr/2014ENMP0094

Chicago Manual of Style (16^th Edition):

Thielleux, Delphine. “Choix des Matériaux et des procédés de mise en forme pour l’allègement des boîtiers d’électronique de puissance des véhicules électriques : Materials selection and manufacturing process development for power electronic control casing of electric vehicles.” 2014. Doctoral Dissertation, Paris, ENMP. Accessed January 23, 2021. http://www.theses.fr/2014ENMP0094.

MLA Handbook (7^th Edition):

Thielleux, Delphine. “Choix des Matériaux et des procédés de mise en forme pour l’allègement des boîtiers d’électronique de puissance des véhicules électriques : Materials selection and manufacturing process development for power electronic control casing of electric vehicles.” 2014. Web. 23 Jan 2021.

Vancouver:

Thielleux D. Choix des Matériaux et des procédés de mise en forme pour l’allègement des boîtiers d’électronique de puissance des véhicules électriques : Materials selection and manufacturing process development for power electronic control casing of electric vehicles. [Internet] [Doctoral dissertation]. Paris, ENMP; 2014. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2014ENMP0094.

Council of Science Editors:

Thielleux D. Choix des Matériaux et des procédés de mise en forme pour l’allègement des boîtiers d’électronique de puissance des véhicules électriques : Materials selection and manufacturing process development for power electronic control casing of electric vehicles. [Doctoral Dissertation]. Paris, ENMP; 2014. Available from: http://www.theses.fr/2014ENMP0094

University of Oxford

25. Zhang, De-Liang. Heterogeneous nucleation of solidification of metals and alloys.

Degree: PhD, 1990, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:5116b367-b1aa-472a-b992-b1fb5f96b76d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276839

► The main aim of this work is to investigate heterogeneous nucleation of solidification of metals and alloys by a combination of differential scanning calorimetry and… (more)

▼ The main aim of this work is to investigate heterogeneous nucleation of solidification of metals and alloys by a combination of differential scanning calorimetry and transmission electron microscopy using a newly modified entrained particle technique. Attention is focused on investigating (a) heterogeneous nucleation of Cd, In and Pb particle solidification by Al in rapidly solidified Al-Cd, Al-In and Al-Pb binary alloys; (b) effects of various ternary additions such as Mg, Ge and Si on heterogenous nucleation of solidification of Cd and Pb solidification by Al; (c) heterogenous nucleation of solidification of Si by solid Al in hypoeutectic Al-Si alloys. In addition, the melting behaviour of Cd, In and Pb particles embedded in an Al matrix is investigated. The rapidly solidified microstructures of melt spun Al-Cd, Al-In and Al-Pb alloys consist of faceted 5-200nm diameter Cd, In and Pb particles homogeneously distributed throughout an Al matrix. Cd particles exhibit an orientation relationship with the Al matrix which can be described as {111}_Al//{0001}_Cd and andlt;110andgt;_Al//andlt;112and#773;0andgt;_Cd, and In and Pb particles exhibit a near cube-cube and cube-cube orientation relationship with the Al matrix respectively. Cd, In and Pb particles embedded in the Al matrix exhibit distorted truncated octahedral or truncated octahedral shapes surrounded by {111}_Al and {100}_Al facets. The solid Al-solid Cd, solid Al-solid In surface energy anisotropies are constant over the temperature range between room temperature and Cd and In melting points respectively. The solid Al-liquid Cd and solid Al-liquid In surface energy anisotropies decrease with increasing temperature above Cd and In melting points. Solidification of Cd, In, Pb particles embedded in an Al matrix is nucleated catalytically by the surrounding Al matrix on the {111}_Al faceted surfaces with an undercooling of 56, 13 and 22K and a contact angle of 42°, 27° and 21° for Cd, In and Pb particles respectively. Addition of Mg to Cd particles embedded in Al increases the lattice disregistry across the nucleating plane, but decreases the undercooling before the onset of Cd(Mg) particle solidification. Addition of Ge to Al decreases the lattice disregistry across the nucleating plane, but increases the undercooling before the onset of Pb particle solidification embedded in the Al(Ge) matrix. These results indicate that chemical interactions dominate over structural factors in determining the catalytic efficiency of nucleation solification in Al-Cd-Mg and Al-Pb-Ge alloys. Contact between Si precipitates and Pb particles embedded in an Al matrix decreases the undercooling before the onset of Pb particle solidification. The equilibrium melting point of Cd particle in the melt spun Al-Cd alloy is depressed because of capillarity, and the depression of equilibrium melting point increases with decreasing particle size. In the melt spun Al-In and Al-Pb alloys, however, most of the In and Pb…

Subjects/Keywords: 669; Alloys : Solidification : Metals : Rapid solidification processing : Nucleation

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APA (6^th Edition):

Zhang, D. (1990). Heterogeneous nucleation of solidification of metals and alloys. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:5116b367-b1aa-472a-b992-b1fb5f96b76d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276839

Chicago Manual of Style (16^th Edition):

Zhang, De-Liang. “Heterogeneous nucleation of solidification of metals and alloys.” 1990. Doctoral Dissertation, University of Oxford. Accessed January 23, 2021. http://ora.ox.ac.uk/objects/uuid:5116b367-b1aa-472a-b992-b1fb5f96b76d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276839.

MLA Handbook (7^th Edition):

Zhang, De-Liang. “Heterogeneous nucleation of solidification of metals and alloys.” 1990. Web. 23 Jan 2021.

Vancouver:

Zhang D. Heterogeneous nucleation of solidification of metals and alloys. [Internet] [Doctoral dissertation]. University of Oxford; 1990. [cited 2021 Jan 23]. Available from: http://ora.ox.ac.uk/objects/uuid:5116b367-b1aa-472a-b992-b1fb5f96b76d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276839.

Council of Science Editors:

Zhang D. Heterogeneous nucleation of solidification of metals and alloys. [Doctoral Dissertation]. University of Oxford; 1990. Available from: http://ora.ox.ac.uk/objects/uuid:5116b367-b1aa-472a-b992-b1fb5f96b76d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276839

26. Wang, Jun. Alliages base Cobalt en surfusion sous champ magnétique intense : propriétés magnétiques et comportement à la solidification : Magnetic Properties and Solidification Behavior of Undercooled Co Based Alloys Under High Magnetic Field.

Degree: Docteur es, Physique, 2012, Grenoble; 216 Northwestern Polytechnic Univ

URL: http://www.theses.fr/2012GRENY070

►

Ce travail est dédié à l'étude de l'effet des champs magnétiques sur les propriétés magnétiques et le comportement à la solidification d'alliages à base de… (more)

▼

Ce travail est dédié à l'étude de l'effet des champs magnétiques sur les propriétés magnétiques et le comportement à la solidification d'alliages à base de Cobalt en surfusion sous champ magnétique intense. Les alliages à base Co sont d'excellents candidats pour obtenir une surfusion en dessous ou proche du point de Curie sous champ intense en raison du faible écart entre ce point de Curie et la température du liquidus. Dans cette étude, un dispositif haute température de surfusion intégrant une mesure magnétique a été construit dans un aimant supraconducteur, et est utilisé pour la mesure in situ de l'aimantation de liquides surfondus et pour l'étude du sur-refroidissement et de l'évolution de la microstructure de solidification en champ intense. Le cobalt liquide en surfusion est fortement magnétique sous champ, et son aimantation est même supérieure à celle du solide au chauffage à la même température. L'aimantation de l'alliage proche eutectique Co-B en surfusion dépend de la température de surchauffe, tandis que le Co-Sn en surfusion est toujours paramagnétique. La surfusion moyenne et l'étendue de la recalescence de différents métaux et alliages est affectée par un champ externe. En champ magnétique uniforme, la surfusion du Cuivre est amplifiée, tandis que la surfusion du Cobalt et de Co-Sn reste identique. Cependant, l'étendue de la recalescence du Cobalt et de Co-Sn est réduite, et l'effet est d'autant plus important pour des teneurs supérieures en Cobalt. Le champ magnétique promeut la précipitation de la phase dendritique a-Co et la formation d'eutectique anormal dans la microstructure des alliages Co-Sn surfondus. Les processus d'évolution de la microstructure sont affectés par le champ magnétique, et dépendent de l'intensité du champ et de la surfusion. Ce travail offre de nouveaux horizons dans l'étude des propriétés magnétiques d'alliages métalliques en forte surfusion et dans l'étude de la solidification hors équilibre sous champ magnétique intense.

This work is devoted to the investigation of the magnetic field effect on the magnetic properties and solidification behavior of undercooled Co based alloys in high magnetic field. Co based alloys are promising candidates to be undercooled below or approaching their Curie point in strong magnetic field due to their small temperature difference between liquid line and Curie point. In this dissertation, a high temperature undercooling facility with magnetization measurement system is built in a superconducting magnet, and is used for in situ measurement of the magnetization of the undercooled melts and study the undercoolability and solidification microstructure evolution in magnetic field. The deep undercooled Co melt is strongly magnetized in magnetic fields, and its magnetization is even larger than the magnetization of heated solid at the same temperature. The magnetization of undercooled Co-B near eutectic alloy is related with overheating temperature while the undercooled Co-Sn melt is always in paramagnetic state. Mean undercooling and recalescence…

Advisors/Committee Members: Beaugnon, Eric (thesis director).

Subjects/Keywords: Champs magnétiques intenses; Surfusion; Solidification; Transition ferromagnétiue; Alliages base Co; High magnetic fields; Undercooling,; Solidification; Ferromagnetic transition; Co based alloys

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wang, J. (2012). Alliages base Cobalt en surfusion sous champ magnétique intense : propriétés magnétiques et comportement à la solidification : Magnetic Properties and Solidification Behavior of Undercooled Co Based Alloys Under High Magnetic Field. (Doctoral Dissertation). Grenoble; 216 Northwestern Polytechnic Univ. Retrieved from http://www.theses.fr/2012GRENY070

Chicago Manual of Style (16^th Edition):

Wang, Jun. “Alliages base Cobalt en surfusion sous champ magnétique intense : propriétés magnétiques et comportement à la solidification : Magnetic Properties and Solidification Behavior of Undercooled Co Based Alloys Under High Magnetic Field.” 2012. Doctoral Dissertation, Grenoble; 216 Northwestern Polytechnic Univ. Accessed January 23, 2021. http://www.theses.fr/2012GRENY070.

MLA Handbook (7^th Edition):

Wang, Jun. “Alliages base Cobalt en surfusion sous champ magnétique intense : propriétés magnétiques et comportement à la solidification : Magnetic Properties and Solidification Behavior of Undercooled Co Based Alloys Under High Magnetic Field.” 2012. Web. 23 Jan 2021.

Vancouver:

Wang J. Alliages base Cobalt en surfusion sous champ magnétique intense : propriétés magnétiques et comportement à la solidification : Magnetic Properties and Solidification Behavior of Undercooled Co Based Alloys Under High Magnetic Field. [Internet] [Doctoral dissertation]. Grenoble; 216 Northwestern Polytechnic Univ; 2012. [cited 2021 Jan 23]. Available from: http://www.theses.fr/2012GRENY070.

Council of Science Editors:

Wang J. Alliages base Cobalt en surfusion sous champ magnétique intense : propriétés magnétiques et comportement à la solidification : Magnetic Properties and Solidification Behavior of Undercooled Co Based Alloys Under High Magnetic Field. [Doctoral Dissertation]. Grenoble; 216 Northwestern Polytechnic Univ; 2012. Available from: http://www.theses.fr/2012GRENY070

Indian Institute of Science

27. Kund, Nirmala Kumar. Study Of Solidification And Microstructure Produced By Cooling Slope Method.

Degree: PhD, Faculty of Engineering, 2016, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/2536

► In most casting applications, dendritic microstructure morphology is not desired because it leads to poor mechanical properties. Forced convection causing sufficient shearing in the mushy… (more)

▼ In most casting applications, dendritic microstructure morphology is not desired because it leads to poor mechanical properties. Forced convection causing sufficient shearing in the mushy zone of the partially solidified melt is one of the means to suppress this dendritic growth. The dendrites formed at the solid-liquid interface are detached and carried away due to strong fluid flow to form slurry. This slurry, consisting of rosette or globular particles, provides less resistance to flow even at a high solid fraction and can easily fill the die-cavity. The stated principle is the basis of a new manufacturing technology called “semi-solid forming” (SSF), in which metal alloys are cast in the semi-solid state. This technique has numerous advantages over other existing commercial casting processes, such as reduction of macrosegregation, reduction of porosity and low forming efforts. Among all currently available methods available for large scale production of semisolid slurry, the cooling slope is considered to be a simple but effective method because of its simple design and easy control of process parameters, low equipment and running costs, high production efficiency and reduced inhomogeneity. With this perspective, the primary objective of the present research is to investigate, both experimentally and numerically, convective heat transfer and solidification on a cooling slope, in addition to the study of final microstructure of the cast billets. Some key process parameters are identified, namely pouring temperature, slope angle, slope length, and slope cooling rate. A systematic scaling analysis is performed in order to understand the relative importance of the parameters in influencing the final properties of the slurry and microstructure after solidification. A major part of the present work deals with the development of an experimental set up with careful consideration of the range of process parameters involved by treating the cooling slope as a heat exchanger. Subsequently, a comprehensive numerical model is developed to predict the flow, heat transfer, species concentration solid fraction distribution of aluminum alloy melt while flowing down the cooling slope. The model uses a variable viscosity relation for slurry. The metal-air interface at the top during the melt flow is tracked using a volume of fluid (VOF) method. Solidification is modeled using an enthalpy based approach and a volume averaged technique. The mushy region is modeled as a multi-layered porous medium consisting of fixed columnar dendrites and mobile equiaxed or fragmented grains. In addition, the solidification model also incorporates a fragmentation criterion and solid phase movement. The effects of key process parameters on flow behavior involving velocity distribution, temperature distribution, solid fractions at the slope exit, and macrosegregation, are studied numerically and experimentally for aluminium alloy A356. The resulting microstructures of the cast billets obtained from the experiments are studied and characterized.… Advisors/Committee Members: Dutta, Pradip (advisor).

Subjects/Keywords: Semi Solid Forming; Metal Alloys Casting; Convective Heat Transfer; Solidification; Cooling Slope Method; Aluminium Alloys - Solidification; Alloys - Solidification; Non-Dendritic Microstructures; Semisolid Slurry; Metal Alloys; Semi-solid Forming (SSF); Semi Solid Processing; Metallurgy

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kund, N. K. (2016). Study Of Solidification And Microstructure Produced By Cooling Slope Method. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2536

Chicago Manual of Style (16^th Edition):

Kund, Nirmala Kumar. “Study Of Solidification And Microstructure Produced By Cooling Slope Method.” 2016. Doctoral Dissertation, Indian Institute of Science. Accessed January 23, 2021. http://etd.iisc.ac.in/handle/2005/2536.

MLA Handbook (7^th Edition):

Kund, Nirmala Kumar. “Study Of Solidification And Microstructure Produced By Cooling Slope Method.” 2016. Web. 23 Jan 2021.

Vancouver:

Kund NK. Study Of Solidification And Microstructure Produced By Cooling Slope Method. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2016. [cited 2021 Jan 23]. Available from: http://etd.iisc.ac.in/handle/2005/2536.

Council of Science Editors:

Kund NK. Study Of Solidification And Microstructure Produced By Cooling Slope Method. [Doctoral Dissertation]. Indian Institute of Science; 2016. Available from: http://etd.iisc.ac.in/handle/2005/2536

28. Barber, Lee P. Characterization of the Solidification Behavior and Resultant Microstructures of Magnesium-Aluminum Alloys.

Degree: MS, 2004, Worcester Polytechnic Institute

URL: etd-12234-112022 ; https://digitalcommons.wpi.edu/etd-theses/1148

► "Research and development of magnesium casting alloys depends largely on the metallurgistâ€™s understanding and ability to control the microstructure of the as-cast part. Currently few… (more)

Subjects/Keywords: microstructures; magnesium alloys; solidification behavior; Magnesium alloys; Aluminum castings; Solidification

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APA (6^th Edition):

Barber, L. P. (2004). Characterization of the Solidification Behavior and Resultant Microstructures of Magnesium-Aluminum Alloys. (Thesis). Worcester Polytechnic Institute. Retrieved from etd-12234-112022 ; https://digitalcommons.wpi.edu/etd-theses/1148

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Barber, Lee P. “Characterization of the Solidification Behavior and Resultant Microstructures of Magnesium-Aluminum Alloys.” 2004. Thesis, Worcester Polytechnic Institute. Accessed January 23, 2021. etd-12234-112022 ; https://digitalcommons.wpi.edu/etd-theses/1148.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Barber, Lee P. “Characterization of the Solidification Behavior and Resultant Microstructures of Magnesium-Aluminum Alloys.” 2004. Web. 23 Jan 2021.

Vancouver:

Barber LP. Characterization of the Solidification Behavior and Resultant Microstructures of Magnesium-Aluminum Alloys. [Internet] [Thesis]. Worcester Polytechnic Institute; 2004. [cited 2021 Jan 23]. Available from: etd-12234-112022 ; https://digitalcommons.wpi.edu/etd-theses/1148.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Barber LP. Characterization of the Solidification Behavior and Resultant Microstructures of Magnesium-Aluminum Alloys. [Thesis]. Worcester Polytechnic Institute; 2004. Available from: etd-12234-112022 ; https://digitalcommons.wpi.edu/etd-theses/1148

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade do Rio Grande do Sul

29. Bartex, Sérgio Luiz Telles. Influência do superaquecimento na formação de fases de uma liga de magnésio contendo elemento Terras Raras.

Degree: 2012, Universidade do Rio Grande do Sul

URL: http://hdl.handle.net/10183/61152

►

O objetivo principal desse trabalho é estudar o processo de solidificação e da formação de fases de uma liga de magnésio contendo elemento Terras Raras… (more)

▼

O objetivo principal desse trabalho é estudar o processo de solidificação e da formação de fases de uma liga de magnésio contendo elemento Terras Raras (Mg-6Al-3La-1Ca), submetida a diferentes níveis de superaquecimento. Para isso, foi utilizado um sistema de solidificação unidirecional ascendente com atmosfera controlada. Termopares foram utilizados para monitorar a evolução térmica dos lingotes, que foram resfriados de forma lenta (convecção natural) e de forma rápida (convecção forçada com água refrigerando a base). Pôde-se, então, determinar as temperaturas de transformação da liga (temperaturas solidus e liquidus). Além disso, foram identificadas as formações da matriz α-Mg, dos compostos de forma acicular Al11La3, e dos eutéticos Mg2Ca e (Al,Mg)2Ca, além de uma fina estrutura dispersa pela matriz indicando ser provavelmente Al2Ca. O superaquecimento mostrou forte influência na morfologia quando aliado ao resfriamento rápido. Para maiores valores de superaquecimento a formação de fases contendo Lantânio foi majorada e a formação de estruturas eutéticas contendo Cálcio foi retardada. Equações correlacionando parâmetros struturais e térmicos foram geradas mostrando conformidade com a literatura.

This work aimed to study the solidification process and phase formation of a magnesium alloy containing rare earth elements (Mg-6Al-3La-1CA) subjected under different values of superheating. For this, it was used an unidirectional solidification system with a controlled atmosphere. Thermocouples were used to follow up the thermal evolution of the ingots, in both, slow cooling condition (using natural convection) and fast cooling condition (using water in the base to cooling the ingots). So it was then determined the transformation temperatures of the alloy (solidus and liquidus temperatures). Furthermore, it was identified the formations of α-Mg matrix, the compounds of Al11La3 (acicular form), and the eutectic Mg2Ca and (Al, Mg)2Ca, and a fine structure dispersed through the specimen indicating, probably, to be Al2Ca. Superheating has showed strong influence on morphology when combined with rapid cooling. For larger values of superheating the formation of phases containing lanthanum was increased and the formation of eutectic structures containing calcium was delayed. Correlation between thermal parameters and microstructure were made and the results agreement with the literature.

Advisors/Committee Members: Spim Junior, Jaime Alvares.

Subjects/Keywords: Solidification; Ligas de magnésio; Light alloys; Análise térmica; Solidificação; Thermal analysis; Terras raras; Microstructure; Magnesium

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bartex, S. L. T. (2012). Influência do superaquecimento na formação de fases de uma liga de magnésio contendo elemento Terras Raras. (Thesis). Universidade do Rio Grande do Sul. Retrieved from http://hdl.handle.net/10183/61152

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Bartex, Sérgio Luiz Telles. “Influência do superaquecimento na formação de fases de uma liga de magnésio contendo elemento Terras Raras.” 2012. Thesis, Universidade do Rio Grande do Sul. Accessed January 23, 2021. http://hdl.handle.net/10183/61152.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Bartex, Sérgio Luiz Telles. “Influência do superaquecimento na formação de fases de uma liga de magnésio contendo elemento Terras Raras.” 2012. Web. 23 Jan 2021.

Vancouver:

Bartex SLT. Influência do superaquecimento na formação de fases de uma liga de magnésio contendo elemento Terras Raras. [Internet] [Thesis]. Universidade do Rio Grande do Sul; 2012. [cited 2021 Jan 23]. Available from: http://hdl.handle.net/10183/61152.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Bartex SLT. Influência do superaquecimento na formação de fases de uma liga de magnésio contendo elemento Terras Raras. [Thesis]. Universidade do Rio Grande do Sul; 2012. Available from: http://hdl.handle.net/10183/61152

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade Estadual de Campinas

30. Brito, Crystopher Cardoso de, 1987-. Parâmetros térmicos e microestruturais na solidificação transitória de Ligas Al-Mg e Al-Mg-Si e correlação com resistências mecânicas e à corrosão: Thermal and microstructural parameters in the transient solidification of Al-Mg and Al-Mg-Si alloys and correlation with mechanical and corrosion resistances.

Degree: 2016, Universidade Estadual de Campinas

URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/265695

► Abstract: The mechanical characteristics (strength under static and dynamic loading; wear resistance) and chemical characteristics (corrosion resistance) of as solidified metallic components depend on the… (more)

▼ Abstract: The mechanical characteristics (strength under static and dynamic loading; wear resistance) and chemical characteristics (corrosion resistance) of as solidified metallic components depend on the microstructural arrangement, i.e. grain size and cellular, dendritic, interphase spacings; non-homogeneity of chemical composition; size, morphology and distribution of inclusions; porosity, etc. Additionally to the barriers to slip formed by the grain boundaries there are also obstacles located in intercellular and interdendritic regions. The development of correlations between the as-solidified microstructure and the corresponding properties can be a complex task, which depends on careful experimental development with a view to determining accurate solidification thermal parameters. The present study aims to develop a theoretical/ experimental analysis dealing with the effects of transient thermal parameters in the solidification of Al-Mg and Al-Mg-Si alloys on the microstructure development and on macrosegregation profiles. Correlations between microstructural parameters and mechanical and corrosion resistances will be established with a view to permitting solidification operational conditions to be pre-programmed in order to allow the casting to attain a determined level of final properties. Therefore, directional solidification experiments both in transient (vertical upward and downward) and steady-state regimes (Bridgman growth) were carried out. For binary Al-3Mg and Al-6,5Mg and ternary Al-3Mg-1Si and Al-6,5Mg-1Si alloys, no evidence of macrosegregation has been found, not even for cases of downward directional solidification. With the exception of the Al-3Mg-1Si alloy, all the alloys experimentally examined depicted a dendritic Al-rich matrix along the whole range of experimental cooling rates ( dT/dt ).In contrast, the Al-3Mg-1Si alloy showed cellular morphology for 0,005 < dT/dt > 2K/s, and dendritic for 0,03 > dT/dt < 0,8 K/s. These results characterized the occurrence of a reversal cellular/dendritic transition (high cooling rates cells), which is rarely reported in the literature for metallic alloys. Experimental growth laws relating cellular and dendritic spacings (primary, secondary and tertiary) to solidification thermal parameters (growth and cooling rates) have been proposed for any alloy examined. Mechanical properties (hardness and tensile properties) and corrosion resistance have been examined for the Al-3Mg and Al-3Mg-1Si alloys. The Vickers microhardness of the ternary alloy is shown to the highest due to a more complex microstructure and a higher content of Mg2Si and Al-Fe-Si(-Mg) intermetallics. The best combination ultimate tensile strength/elongation to fracture is shown to be associated with the cellular microstructure of the Al-3Mg-Si alloy, despite the higher values of elongation of the Al-3Mg alloy. Hall-Petch type experimental laws are proposed relating these tensile properties and Vickers microhardness to the length scale of the microstructure, more specifically to the cellular and… Advisors/Committee Members: UNIVERSIDADE ESTADUAL DE CAMPINAS (CRUESP), Garcia, Amauri, 1949- (advisor), Spinelli, Jose Eduardo (coadvisor), Universidade Estadual de Campinas. Faculdade de Engenharia Mecânica (institution), Programa de Pós-Graduação em Engenharia Mecânica (nameofprogram), Santos, Rezende Gomes dos (committee member), Zavaglia, Cecília Amélia de Carvalho (committee member), Souza, Eduardo Netto de (committee member), Pinto, Maria Aparecida (committee member).

Subjects/Keywords: Solidificação; Ligas de alumínio; Microestrutura; Resistência mecânica; Corrosão; Solidification; Aluminum alloys; Microstructure; Mechanical resistance; Corrosion

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Brito, Crystopher Cardoso de, 1. (2016). Parâmetros térmicos e microestruturais na solidificação transitória de Ligas Al-Mg e Al-Mg-Si e correlação com resistências mecânicas e à corrosão: Thermal and microstructural parameters in the transient solidification of Al-Mg and Al-Mg-Si alloys and correlation with mechanical and corrosion resistances. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/265695

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Brito, Crystopher Cardoso de, 1987-. “Parâmetros térmicos e microestruturais na solidificação transitória de Ligas Al-Mg e Al-Mg-Si e correlação com resistências mecânicas e à corrosão: Thermal and microstructural parameters in the transient solidification of Al-Mg and Al-Mg-Si alloys and correlation with mechanical and corrosion resistances.” 2016. Thesis, Universidade Estadual de Campinas. Accessed January 23, 2021. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265695.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Brito, Crystopher Cardoso de, 1987-. “Parâmetros térmicos e microestruturais na solidificação transitória de Ligas Al-Mg e Al-Mg-Si e correlação com resistências mecânicas e à corrosão: Thermal and microstructural parameters in the transient solidification of Al-Mg and Al-Mg-Si alloys and correlation with mechanical and corrosion resistances.” 2016. Web. 23 Jan 2021.

Vancouver:

Brito, Crystopher Cardoso de 1. Parâmetros térmicos e microestruturais na solidificação transitória de Ligas Al-Mg e Al-Mg-Si e correlação com resistências mecânicas e à corrosão: Thermal and microstructural parameters in the transient solidification of Al-Mg and Al-Mg-Si alloys and correlation with mechanical and corrosion resistances. [Internet] [Thesis]. Universidade Estadual de Campinas; 2016. [cited 2021 Jan 23]. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/265695.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Brito, Crystopher Cardoso de 1. Parâmetros térmicos e microestruturais na solidificação transitória de Ligas Al-Mg e Al-Mg-Si e correlação com resistências mecânicas e à corrosão: Thermal and microstructural parameters in the transient solidification of Al-Mg and Al-Mg-Si alloys and correlation with mechanical and corrosion resistances. [Thesis]. Universidade Estadual de Campinas; 2016. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/265695

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Open Access Theses and Dissertations