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University of Hong Kong
1.
蘇玫妮; Su, Meini.
Behaviour and design of aluminium alloy structural
elements.
Degree: PhD, 2014, University of Hong Kong
URL: Su,
M.
[蘇玫妮].
(2014).
Behaviour
and
design
of
aluminium
alloy
structural
elements.
(Thesis).
University
of
Hong
Kong,
Pokfulam,
Hong
Kong
SAR.
Retrieved
from
http://dx.doi.org/10.5353/th_b5328036 
;
http://dx.doi.org/10.5353/th_b5328036
;
http://hdl.handle.net/10722/206728
► Aluminium alloys are nonlinear metallic materials with continuous stress-strain curves that are not well represented by the simplified elastic, perfectly plastic material model used in…
(more)
▼ Aluminium
alloys are nonlinear metallic materials
with continuous stress-strain curves that are not well represented
by the simplified elastic, perfectly plastic material model used in
most existing design specifications. The aims of this study are to
develop a more efficient design method for aluminium alloy
structures by rationally exploiting strain hardening. The key
components of this study include laboratory testing, numerical
modelling and development of design guidance for aluminium alloy
structures.
As part of the present study, the experimental
programme included tests on 11 stub columns, 40 simply supported
beams, 46 continuous beams and corresponding tensile coupon tests.
Numerical investigations of aluminium alloy simply supported beams
and continuous beams were also conducted. The validated finite
element models were used for extensive parametric studies,
generating 96 results for beams under three-point bending, 96 under
four-point bending and 210 for continuous beams. The experiments
and numerical simulations have shown the following key features of
the inelastic behaviour of aluminium alloy structural elements: (1)
the significance of strain hardening, indicated by the ultimate
stress over the yield stress, could be up to 50%; (2) non-slender
section capacities could be generally up to 40% higher than the
yield limits in compression, and 50% greater than the plastic
moments in bending; (3) the experimental and numerical ultimate
loads of continuous beams on non-slender sections go beyond the
calculated loads corresponding to the occurrence of the first hinge
by more than 10%.
Previous experimental data on aluminium alloy
stub columns and simply supported beams were also collected. These
collected test data were used together with the newly generated
experimental and numerical results obtained from this study,
totalling about 900 data, to assess the design predictions of the
American, Australian/New Zealand and European specifications. On
average, the existing design methods under-estimated the capacity
of aluminium alloy stub columns by around 15%~22%, simply supported
beams by around 18%~40% and continuous beams by around 27% ~ 50%.
Existing section classification limits in Eurocode 9 (2007) were
also assessed, and while they were found to be safe, some improved
limits were proposed.
The combined experimental and numerical
results were used to develop and calibrate a new design method,
termed the continuous strength method (CSM). Two key components of
the CSM – a base curve and a bi-linear material model for aluminium
alloys have been proposed in this study. Global plastic analysis
allowing for moment redistribution has also been adopted in the
CSM. Unlike current practices, the CSM has the merits of adopting
the continuous treatment for the cross-section deformation
response, rationally exploiting the available capacity beyond the
yield limit and reasonably allowing for redistributing the internal
forces.
The capacity predictions of aluminium alloy structural
members have been improved by more…
Advisors/Committee Members: Young, B.
Subjects/Keywords: Aluminum alloys
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APA (6th Edition):
蘇玫妮; Su, M. (2014). Behaviour and design of aluminium alloy structural
elements. (Doctoral Dissertation). University of Hong Kong. Retrieved from Su, M. [蘇玫妮]. (2014). Behaviour and design of aluminium alloy structural elements. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5328036 ; http://dx.doi.org/10.5353/th_b5328036 ; http://hdl.handle.net/10722/206728
Chicago Manual of Style (16th Edition):
蘇玫妮; Su, Meini. “Behaviour and design of aluminium alloy structural
elements.” 2014. Doctoral Dissertation, University of Hong Kong. Accessed January 23, 2020.
Su, M. [蘇玫妮]. (2014). Behaviour and design of aluminium alloy structural elements. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5328036 ; http://dx.doi.org/10.5353/th_b5328036 ; http://hdl.handle.net/10722/206728.
MLA Handbook (7th Edition):
蘇玫妮; Su, Meini. “Behaviour and design of aluminium alloy structural
elements.” 2014. Web. 23 Jan 2020.
Vancouver:
蘇玫妮; Su M. Behaviour and design of aluminium alloy structural
elements. [Internet] [Doctoral dissertation]. University of Hong Kong; 2014. [cited 2020 Jan 23].
Available from: Su, M. [蘇玫妮]. (2014). Behaviour and design of aluminium alloy structural elements. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5328036 ; http://dx.doi.org/10.5353/th_b5328036 ; http://hdl.handle.net/10722/206728.
Council of Science Editors:
蘇玫妮; Su M. Behaviour and design of aluminium alloy structural
elements. [Doctoral Dissertation]. University of Hong Kong; 2014. Available from: Su, M. [蘇玫妮]. (2014). Behaviour and design of aluminium alloy structural elements. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5328036 ; http://dx.doi.org/10.5353/th_b5328036 ; http://hdl.handle.net/10722/206728
2.
Du, Ningning.
Multi-scale Modeling of Deformation and Failure Mechanisms
of Al Alloys at Elevated Temperature.
Degree: PhD, Division of Engineering. Mechanics of
Solids, 2009, Brown University
URL: https://repository.library.brown.edu/studio/item/bdr:193/
► When deformed at elevated temperature and slow strain rates, some Al alloys exhibits superplasticity, the ability to sustain very large tensile elongations (sometimes over 1000%)…
(more)
▼ When deformed at elevated temperature and slow strain
rates, some Al
alloys exhibits superplasticity, the ability to
sustain very large tensile elongations (sometimes over 1000%) prior
to failure in a generally isotropic manner. This property has been
exploited in industrial manufacturing processes such as
superplastic forming and quick plastic forming. This dissertation
investigated some aspects that are related to the deformation and
failure of Al
alloys at elevated temperature with numerical
simulations of multiple time and length scales. First, a finite
element method rigorously accounts for three main deformation
mechanisms in superplasticity, namely the grain interior
plasticity, grain boundary diffusion and grain boundary sliding is
given. The method was used to predict the constitutive response and
contribution of each mechanism to the total plastic strain based on
microstructures of an assembly of grains. The microstructure finite
element model is also used to conduct a systematic study of the
mechanisms of void growth in polycrystalline Al AA5083 during
elevated temperature straining. Second, to further understand the
nature of grain boundary sliding, molecular dynamics simulations
are used to investigate the effect of vacancies, Si and Mg
impurities in the Al grain boundaries on grain boundary sliding.
Finally, a multi-scale approach that links the microstructure based
finite element model to the continuum scale finite element
simulations of elevated temperature forming of Al
alloys is
proposed and used to study the bulge forming process. The work of
this dissertation should be useful toward making reliable
quantitive predictions of Al and similar superplastic
alloys, and
ultimately modifying and designing engineered superplastic
materials that is suitable for various purposes.
Advisors/Committee Members: Bower, Allan (director), Gao, Huajian (reader), Chason, Eric (reader).
Subjects/Keywords: Al alloys
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APA (6th Edition):
Du, N. (2009). Multi-scale Modeling of Deformation and Failure Mechanisms
of Al Alloys at Elevated Temperature. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:193/
Chicago Manual of Style (16th Edition):
Du, Ningning. “Multi-scale Modeling of Deformation and Failure Mechanisms
of Al Alloys at Elevated Temperature.” 2009. Doctoral Dissertation, Brown University. Accessed January 23, 2020.
https://repository.library.brown.edu/studio/item/bdr:193/.
MLA Handbook (7th Edition):
Du, Ningning. “Multi-scale Modeling of Deformation and Failure Mechanisms
of Al Alloys at Elevated Temperature.” 2009. Web. 23 Jan 2020.
Vancouver:
Du N. Multi-scale Modeling of Deformation and Failure Mechanisms
of Al Alloys at Elevated Temperature. [Internet] [Doctoral dissertation]. Brown University; 2009. [cited 2020 Jan 23].
Available from: https://repository.library.brown.edu/studio/item/bdr:193/.
Council of Science Editors:
Du N. Multi-scale Modeling of Deformation and Failure Mechanisms
of Al Alloys at Elevated Temperature. [Doctoral Dissertation]. Brown University; 2009. Available from: https://repository.library.brown.edu/studio/item/bdr:193/
Oregon State University
3.
Biskey, John Wesley.
The development of Fe-Cr-C based alloys for high wear and high impact applications.
Degree: MS, Mechanical and Metallurgical Engineering, 1975, Oregon State University
URL: http://hdl.handle.net/1957/44395
► The structure, hardness, and impact strength of high chromium cast irons was investigated. From the Fe- Cr- C phase diagram, a composition with 74.8 wt%…
(more)
▼ The structure, hardness, and impact strength of high chromium
cast irons was investigated. From the Fe- Cr- C phase diagram,
a composition with 74.8 wt% Fe, 21.5 wt% Cr, and 3.7 wt% was
selected along the austenite-M₇C₃ eutectic trough. This composition
was bracketed by others with slightly different amounts of iron,
chromium, and carbon. These basic
alloys were then modified
with additions of manganese, nickel, titanium, and silicon.
Hardness measurements were made on small arc melted
buttons and on cast impact specimens. The hardness of these
alloys
varied from Rc 45 (BHN 425) to Rc 65 (BHN 750).
The impact specimens were round pins for a modified Izod
test. Most
alloys had impact strengths from 2 to 3 ft-lb. However,
a slightly hypoeutectic alloy had an impact strength of 7 ft-lb at
room temperature and 5 ft-lb at -40°F (-40°C). This was obtained with an alloy of 74 wt% Fe, 18.8 wt% Cr, 3. 7 wt% C, 2 wt% Mn,
2 wt% Ni, and 0.5 wt% Si.
Based on these limited tests, it was concluded that it should
be possible to develop a moderately tough Fe-Cr-C based cast iron.
Alloys with this toughness, combined with the high hardness,
should find applications in the mining and ore handling industry.
Advisors/Committee Members: Paasche, Olaf G. (advisor).
Subjects/Keywords: Alloys
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APA (6th Edition):
Biskey, J. W. (1975). The development of Fe-Cr-C based alloys for high wear and high impact applications. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/44395
Chicago Manual of Style (16th Edition):
Biskey, John Wesley. “The development of Fe-Cr-C based alloys for high wear and high impact applications.” 1975. Masters Thesis, Oregon State University. Accessed January 23, 2020.
http://hdl.handle.net/1957/44395.
MLA Handbook (7th Edition):
Biskey, John Wesley. “The development of Fe-Cr-C based alloys for high wear and high impact applications.” 1975. Web. 23 Jan 2020.
Vancouver:
Biskey JW. The development of Fe-Cr-C based alloys for high wear and high impact applications. [Internet] [Masters thesis]. Oregon State University; 1975. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/1957/44395.
Council of Science Editors:
Biskey JW. The development of Fe-Cr-C based alloys for high wear and high impact applications. [Masters Thesis]. Oregon State University; 1975. Available from: http://hdl.handle.net/1957/44395
Michigan State University
5.
Burnett, James Robert.
Short-time heat treating characteristics of a binary copper-beryllium alloy.
Degree: MS, 1949, Michigan State University
URL: http://etd.lib.msu.edu/islandora/object/etd:9874
Subjects/Keywords: Alloys
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APA (6th Edition):
Burnett, J. R. (1949). Short-time heat treating characteristics of a binary copper-beryllium alloy. (Masters Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:9874
Chicago Manual of Style (16th Edition):
Burnett, James Robert. “Short-time heat treating characteristics of a binary copper-beryllium alloy.” 1949. Masters Thesis, Michigan State University. Accessed January 23, 2020.
http://etd.lib.msu.edu/islandora/object/etd:9874.
MLA Handbook (7th Edition):
Burnett, James Robert. “Short-time heat treating characteristics of a binary copper-beryllium alloy.” 1949. Web. 23 Jan 2020.
Vancouver:
Burnett JR. Short-time heat treating characteristics of a binary copper-beryllium alloy. [Internet] [Masters thesis]. Michigan State University; 1949. [cited 2020 Jan 23].
Available from: http://etd.lib.msu.edu/islandora/object/etd:9874.
Council of Science Editors:
Burnett JR. Short-time heat treating characteristics of a binary copper-beryllium alloy. [Masters Thesis]. Michigan State University; 1949. Available from: http://etd.lib.msu.edu/islandora/object/etd:9874
University of Limerick
6.
Richardson, David.
Nanotubes prepared by electroless deposition: investigation of the nanostructure formation mechanism and characterisation of physical properties.
Degree: 2015, University of Limerick
URL: http://hdl.handle.net/10344/8104
► In this research, we investigate electrolessly deposited nanotubes due to their unique associated magnetic and catalytic properties. The main challenge associated with electroless deposition is…
(more)
▼ In this research, we investigate electrolessly deposited nanotubes due to their unique associated magnetic and catalytic properties. The main challenge associated with electroless deposition is the formation of a nanotube structure with a uniform wall thickness. In this study, we investigate the electroless deposition process of nanotubes within a polycarbonate membrane. By identifying the conditions required to ensure a kinetically controlled deposition process, we achieve the formation of continuous nanotubes with a uniform wall thickness.
Electrolessly deposited
alloys containing Ni, Fe and Co are magnetic and have many potential applications in future technologies. In this work, we investigate the magnetic properties of a series of
alloys including Ni-B, Ni-Fe-B, Co-B and Ni-Cu-B nanotube structures. We establish the relationships between the magnetic properties of the nanostructure and their structure and compositional parameters. We also characterise the magnetic reversal mechanisms associated with the nanotube structure, which depend on the alloy used. We achieve a maximum specific magnetisation of 84.3 J T-1 kg-1 and a minimum coercivity of 0.003 T.
Alloyed deposits containing B can be used to catalyse hydrogen release from an alkaline NaBH4 solution. In this study, a variety of nanostructured
alloys, including Ni-B, Co-B, NiCu-B, NiFe-B and NiCo-B and CoNiFe-B are investigated as catalysts for hydrogen generation. We show that nanostructured catalysts have larger hydrogen generation than metallic films with a maximum hydrogen generation rate of 10,800 ml min-1 g-1.
Advisors/Committee Members: Rhen, Fernando M.F..
Subjects/Keywords: nanotubes; alloys
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APA (6th Edition):
Richardson, D. (2015). Nanotubes prepared by electroless deposition: investigation of the nanostructure formation mechanism and characterisation of physical properties. (Thesis). University of Limerick. Retrieved from http://hdl.handle.net/10344/8104
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Richardson, David. “Nanotubes prepared by electroless deposition: investigation of the nanostructure formation mechanism and characterisation of physical properties.” 2015. Thesis, University of Limerick. Accessed January 23, 2020.
http://hdl.handle.net/10344/8104.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Richardson, David. “Nanotubes prepared by electroless deposition: investigation of the nanostructure formation mechanism and characterisation of physical properties.” 2015. Web. 23 Jan 2020.
Vancouver:
Richardson D. Nanotubes prepared by electroless deposition: investigation of the nanostructure formation mechanism and characterisation of physical properties. [Internet] [Thesis]. University of Limerick; 2015. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/10344/8104.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Richardson D. Nanotubes prepared by electroless deposition: investigation of the nanostructure formation mechanism and characterisation of physical properties. [Thesis]. University of Limerick; 2015. Available from: http://hdl.handle.net/10344/8104
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Indian Institute of Science
7.
Shrikant, Joshi Sameehan.
Development Of Cast Magnesium Alloys With Improved Strength.
Degree: 2012, Indian Institute of Science
URL: http://hdl.handle.net/2005/2311
► Aim of the present work was to explore the possibility of improving strength of cast Mg by alloying additions, viz., Si and Zn+Al. All the…
(more)
▼ Aim of the present work was to explore the possibility of improving strength of cast Mg by alloying additions, viz., Si and Zn+Al. All the
alloys were produced by squeeze casting technique using squeeze pressure of 12MPa and their microstructure, tensile and corrosion properties were studied.
Mg-Si system was chosen because the intermetallic compound Mg2Si possesses many desirable properties, such as, low density, high hardness, high melting point. Hence, there is scope for improving the strength of Mg by dispersion of primary Mg2Si particles. Addition of Si to Mg resulted in the formation of �-Mg, particles of primary Mg2Si and eutectic as microstructural constituents. The morphology of primary Mg2Si changed from polyhedral shaped particles to dendrites as Si content was increased from 3.57 to 5.5 wt%. Volume fraction of primary Mg2Si increased with increase in Si content. Particle size of primary Mg2Si also increased with increase in silicon content but at the same time it was found to be dependent on melt temperature, i.e., a lower particle size was obtained at higher melt temperatures. Addition of Al and Sr was made to Mg-2Si alloy in order to further increase the strength by solid solution strengthening and refinement/modification of primary Mg2Si particles/eutectic. Addition of 1.2 wt% Al to Mg-2Si alloy resulted in irregular type of morphology of Mg2Si particles and increased particle size. Addition of 0.2 wt% SrtoMg-2Si-1.2Al alloy resulted in slight refinement of primary Mg2Si particles and modification of eutectic. Addition of 0.4 wt% Sr resulted in both refinement and restoration of morphology of Mg2Si particles from irregular to polyhedral shape. This was accompanied by destruction of eutectic, and rods containing Mg, Si, Al and Sr were observed.
The addition of 1.33 wt%Si to Mg resulted in improvement in 0.2%PS by about 80 MPa,UTS by about 40MPa and these values did not change much till the addition of 3.57 wt% Si. A drop in the strength values was observed at Si content of 5.5 wt%,where transition in morphology of primary Mg2Si occurred from polyhedral to dendrite. Addition of Si resulted in reduction in % elongation by about 2%. The addition of Al and Sr did not change the tensile properties of binary Mg-2Si alloy much. It was concluded that the volume fraction and size of primary Mg2Siparticles obtained with Si addition up to 3.57 wt% did not contribute much to strength and the strengthening mainly came from the eutectic present in the matrix. As Si content was increased to 5.5 wt% in order to increase the volume fraction of primary Mg2Si particles, the morphology of Mg2Si changed to dendritic type resulting in reduction in strength. Thus, the maximum increase in strength is achieved at near eutectic composition,i.e.,intheMg-1.33Sialloy,andfurtherincreaseinstrengthdoesnotseem to be feasible with this alloy system. The ductility of all the Mg-Si based
alloys was also low, i.e, 0.5% elongation to fracture or less. Regarding the corrosion behaviour, the addition of Si to Mg deteriorated the corrosion…
Advisors/Committee Members: Kumar, Subodh.
Subjects/Keywords: Magnesium Alloys; Magnesium-Silicon Alloys; Magnesium-Zinc Alloys; Cast Magnesium Alloys; Magnesium Alloys - Microstructure; Magnesium Alloys - Tensile Properties; Magnesium Alloys - Corrosion; Mg Alloys; Mg-Si Alloys; Mg-Zn Alloys; Metallurgy
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APA ·
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Manager
APA (6th Edition):
Shrikant, J. S. (2012). Development Of Cast Magnesium Alloys With Improved Strength. (Thesis). Indian Institute of Science. Retrieved from http://hdl.handle.net/2005/2311
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Shrikant, Joshi Sameehan. “Development Of Cast Magnesium Alloys With Improved Strength.” 2012. Thesis, Indian Institute of Science. Accessed January 23, 2020.
http://hdl.handle.net/2005/2311.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Shrikant, Joshi Sameehan. “Development Of Cast Magnesium Alloys With Improved Strength.” 2012. Web. 23 Jan 2020.
Vancouver:
Shrikant JS. Development Of Cast Magnesium Alloys With Improved Strength. [Internet] [Thesis]. Indian Institute of Science; 2012. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/2005/2311.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Shrikant JS. Development Of Cast Magnesium Alloys With Improved Strength. [Thesis]. Indian Institute of Science; 2012. Available from: http://hdl.handle.net/2005/2311
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Indian Institute of Science
8.
Shrikant, Joshi Sameehan.
Development Of Cast Magnesium Alloys With Improved Strength.
Degree: 2012, Indian Institute of Science
URL: http://etd.iisc.ernet.in/handle/2005/2311
;
http://etd.ncsi.iisc.ernet.in/abstracts/2973/G25100-Abs.pdf
► Aim of the present work was to explore the possibility of improving strength of cast Mg by alloying additions, viz., Si and Zn+Al. All the…
(more)
▼ Aim of the present work was to explore the possibility of improving strength of cast Mg by alloying additions, viz., Si and Zn+Al. All the
alloys were produced by squeeze casting technique using squeeze pressure of 12MPa and their microstructure, tensile and corrosion properties were studied.
Mg-Si system was chosen because the intermetallic compound Mg2Si possesses many desirable properties, such as, low density, high hardness, high melting point. Hence, there is scope for improving the strength of Mg by dispersion of primary Mg2Si particles. Addition of Si to Mg resulted in the formation of �-Mg, particles of primary Mg2Si and eutectic as microstructural constituents. The morphology of primary Mg2Si changed from polyhedral shaped particles to dendrites as Si content was increased from 3.57 to 5.5 wt%. Volume fraction of primary Mg2Si increased with increase in Si content. Particle size of primary Mg2Si also increased with increase in silicon content but at the same time it was found to be dependent on melt temperature, i.e., a lower particle size was obtained at higher melt temperatures. Addition of Al and Sr was made to Mg-2Si alloy in order to further increase the strength by solid solution strengthening and refinement/modification of primary Mg2Si particles/eutectic. Addition of 1.2 wt% Al to Mg-2Si alloy resulted in irregular type of morphology of Mg2Si particles and increased particle size. Addition of 0.2 wt% SrtoMg-2Si-1.2Al alloy resulted in slight refinement of primary Mg2Si particles and modification of eutectic. Addition of 0.4 wt% Sr resulted in both refinement and restoration of morphology of Mg2Si particles from irregular to polyhedral shape. This was accompanied by destruction of eutectic, and rods containing Mg, Si, Al and Sr were observed.
The addition of 1.33 wt%Si to Mg resulted in improvement in 0.2%PS by about 80 MPa,UTS by about 40MPa and these values did not change much till the addition of 3.57 wt% Si. A drop in the strength values was observed at Si content of 5.5 wt%,where transition in morphology of primary Mg2Si occurred from polyhedral to dendrite. Addition of Si resulted in reduction in % elongation by about 2%. The addition of Al and Sr did not change the tensile properties of binary Mg-2Si alloy much. It was concluded that the volume fraction and size of primary Mg2Siparticles obtained with Si addition up to 3.57 wt% did not contribute much to strength and the strengthening mainly came from the eutectic present in the matrix. As Si content was increased to 5.5 wt% in order to increase the volume fraction of primary Mg2Si particles, the morphology of Mg2Si changed to dendritic type resulting in reduction in strength. Thus, the maximum increase in strength is achieved at near eutectic composition,i.e.,intheMg-1.33Sialloy,andfurtherincreaseinstrengthdoesnotseem to be feasible with this alloy system. The ductility of all the Mg-Si based
alloys was also low, i.e, 0.5% elongation to fracture or less. Regarding the corrosion behaviour, the addition of Si to Mg deteriorated the corrosion…
Advisors/Committee Members: Kumar, Subodh.
Subjects/Keywords: Magnesium Alloys; Magnesium-Silicon Alloys; Magnesium-Zinc Alloys; Cast Magnesium Alloys; Magnesium Alloys - Microstructure; Magnesium Alloys - Tensile Properties; Magnesium Alloys - Corrosion; Mg Alloys; Mg-Si Alloys; Mg-Zn Alloys; Metallurgy
Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Shrikant, J. S. (2012). Development Of Cast Magnesium Alloys With Improved Strength. (Thesis). Indian Institute of Science. Retrieved from http://etd.iisc.ernet.in/handle/2005/2311 ; http://etd.ncsi.iisc.ernet.in/abstracts/2973/G25100-Abs.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Shrikant, Joshi Sameehan. “Development Of Cast Magnesium Alloys With Improved Strength.” 2012. Thesis, Indian Institute of Science. Accessed January 23, 2020.
http://etd.iisc.ernet.in/handle/2005/2311 ; http://etd.ncsi.iisc.ernet.in/abstracts/2973/G25100-Abs.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Shrikant, Joshi Sameehan. “Development Of Cast Magnesium Alloys With Improved Strength.” 2012. Web. 23 Jan 2020.
Vancouver:
Shrikant JS. Development Of Cast Magnesium Alloys With Improved Strength. [Internet] [Thesis]. Indian Institute of Science; 2012. [cited 2020 Jan 23].
Available from: http://etd.iisc.ernet.in/handle/2005/2311 ; http://etd.ncsi.iisc.ernet.in/abstracts/2973/G25100-Abs.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Shrikant JS. Development Of Cast Magnesium Alloys With Improved Strength. [Thesis]. Indian Institute of Science; 2012. Available from: http://etd.iisc.ernet.in/handle/2005/2311 ; http://etd.ncsi.iisc.ernet.in/abstracts/2973/G25100-Abs.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Nelson Mandela Metropolitan University
9.
Akinlabi, Esther Titilayo.
Characterisation of dissimilar friction stir welds between 5754 Aluminium alloy and C11000 copper.
Degree: Faculty of Engineering, the Built Environment and Information Technology, 2010, Nelson Mandela Metropolitan University
URL: http://hdl.handle.net/10948/1536
► Friction Stir Welding (FSW) is a solid state welding process invented and patented by The Welding Institute (TWI) in 1991, for joining ferrous and non-ferrous…
(more)
▼ Friction Stir Welding (FSW) is a solid state welding process invented and patented by The Welding Institute (TWI) in 1991, for joining ferrous and non-ferrous materials1. The FSW of Aluminium and its alloys has been commercialised; and recent interest is focused on joining dissimilar materials. However, in order to commercialise the process, research studies are required to characterise and establish process windows. This research work through material characterisation of the welded joints establishes a process window for the Friction Stir welding of 5754 Aluminium Alloy and C11000 Copper. Furthermore, preliminary studies83,85 on the FSW of aluminium and copper have revealed the presence of intermetallic compounds which are detrimental to the weld qualities. This research work is also aimed at establishing process parameters that will result in limited or no intermetallic formation in the weld. The joint integrity of the resulting welds will also be correlated with the input process parameters. Based on the preliminary investigations conducted, a final weld matrix consisting of twenty seven welds was produced by varying the rotational speed between 600 and 1200 rpm, and the feed rate between 50 and 300 mm/min using three different shoulder diameter tools – 15, 18 and 25 mm to compare the heat input into the welds and to achieve the best results. The welds were characterised through microstructural evaluation, tensile testing, microhardness profiling, X-Ray Diffraction analysis, electrical resistivity and statistical analysis – in order to establish the interrelationship between the process parameters and the weld qualities. viii Microstructural evaluation of the weld samples revealed that the interfacial regions are characterised by mixture layers of aluminium and copper; while 33 percent of the tensile samples are within the acceptable range (> 75 percent joint efficiency). High Vickers microhardness values were measured at the joint interfaces, which corresponded with the intermetallic compounds. The Energy Dispersive Spectroscopy analysis revealed the presence of thin layers of intermetallics in nanoscale at the interfacial regions. The diffractograms of the X-Ray Diffraction analysis showed small peaks for intermetallics in some of the welds. Low electrical resistivities were measured at the joint interfaces. The statistical analysis showed that the downward vertical force, (Fz) can significantly influence the resulting weld qualities. An overall summary of the analysis of the weld qualities - with respect to the shoulder diameter tools employed showed that the 18 mm shoulder diameter tool is most appropriate among the three shoulder diameters considered, and a process window of medium spindle speed of 950 rpm and low-to-medium feed rate between 50 and 150 mm/min is established for FSW of Aluminium and Copper. Welds produced at 1200 rpm and 300 mm/min with low heat input did not have intermetallics formed at the joint interface.
Subjects/Keywords: Friction stir welding; Aluminum alloys; Copper alloys
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APA (6th Edition):
Akinlabi, E. T. (2010). Characterisation of dissimilar friction stir welds between 5754 Aluminium alloy and C11000 copper. (Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/1536
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Akinlabi, Esther Titilayo. “Characterisation of dissimilar friction stir welds between 5754 Aluminium alloy and C11000 copper.” 2010. Thesis, Nelson Mandela Metropolitan University. Accessed January 23, 2020.
http://hdl.handle.net/10948/1536.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Akinlabi, Esther Titilayo. “Characterisation of dissimilar friction stir welds between 5754 Aluminium alloy and C11000 copper.” 2010. Web. 23 Jan 2020.
Vancouver:
Akinlabi ET. Characterisation of dissimilar friction stir welds between 5754 Aluminium alloy and C11000 copper. [Internet] [Thesis]. Nelson Mandela Metropolitan University; 2010. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/10948/1536.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Akinlabi ET. Characterisation of dissimilar friction stir welds between 5754 Aluminium alloy and C11000 copper. [Thesis]. Nelson Mandela Metropolitan University; 2010. Available from: http://hdl.handle.net/10948/1536
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of KwaZulu-Natal
10.
[No author].
The structural and mechanical properties of the Pt-Ti and Ir-Ti systems.
Degree: Physics, 2011, University of KwaZulu-Natal
URL: http://hdl.handle.net/10413/7964
► Ab initio plane wave based density functional calculations within the generalised gradient approximation (GGA) have been carried out on a wide range of phases and…
(more)
▼ Ab initio plane wave based density functional calculations within the generalised gradient
approximation (GGA) have been carried out on a wide range of phases and stoichiometries
for the platinum-titanium (Pt-Ti) and iridium-titanium (Ir-Ti) alloy systems, using
the Vienna Ab Initio Simulation Package (VASP) with projector augmented wave (PAW)
potentials.
For all of the phases in this work, the equilibrium structures were found by performing
a full relaxation of the atoms. There were 20 di erent phases considered for varying
atomic percentage compositions for each alloy system. Energy-volume calculations and
heats of formations were used to determined the equilibrium structures at each atomice
percentage composition and to determine if there were high temperature phases at that
composition. The elastic constants and elastic moduli are calculated and the electronic
structure and density of states (DOS) were considered to understand the hardness and
stability properties of the
alloys.
For the Pt-Ti system, the low and high temperature phases at di erent compositions
agreed with previously published results in the literature. Intermediate phases at 50%
were also determined, in agreement with previous results. Alloying Pt with Ti resulted in
a decrease in the bulk modulus, i.e. not adding strength to the metal. However, the shear
modulus increased for most of the
alloys compared to bulk Pt and it was found that in
general, alloying may increase the resistance to shear. PtTi
alloys were found to be ductile
in nature, as with both constituent metals in their bulk form.
In the Ir-Ti system, bulk Ir was found to have the highest bulk, shear and Young's modulus
with each of these values decreasing with increasing percentage Ti in the alloy. IrTi
alloys with 66.7% Ir composition or higher were found to be brittle in nature, similar in
behaviour to bulk Ir;
alloys with a higher percentage concentration of Ti were found to be
ductile.
Advisors/Committee Members: Pierrus, John (advisor).
Subjects/Keywords: Platinum alloys.;
Hard materials.;
Alloys.;
Physics.
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APA (6th Edition):
author], [. (2011). The structural and mechanical properties of the Pt-Ti and Ir-Ti systems.
(Thesis). University of KwaZulu-Natal. Retrieved from http://hdl.handle.net/10413/7964
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
author], [No. “The structural and mechanical properties of the Pt-Ti and Ir-Ti systems.
” 2011. Thesis, University of KwaZulu-Natal. Accessed January 23, 2020.
http://hdl.handle.net/10413/7964.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
author], [No. “The structural and mechanical properties of the Pt-Ti and Ir-Ti systems.
” 2011. Web. 23 Jan 2020.
Vancouver:
author] [. The structural and mechanical properties of the Pt-Ti and Ir-Ti systems.
[Internet] [Thesis]. University of KwaZulu-Natal; 2011. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/10413/7964.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
author] [. The structural and mechanical properties of the Pt-Ti and Ir-Ti systems.
[Thesis]. University of KwaZulu-Natal; 2011. Available from: http://hdl.handle.net/10413/7964
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Urbana-Champaign
11.
Stephenson, Edward Beattie.
Magnetic Properties of Heusler Alloys.
Degree: PhD, University of Illinois at Urbana-Champaign, 1910, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/16433
Subjects/Keywords: Heusler alloys; Alloys
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APA (6th Edition):
Stephenson, E. B. (1910). Magnetic Properties of Heusler Alloys. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/16433
Chicago Manual of Style (16th Edition):
Stephenson, Edward Beattie. “Magnetic Properties of Heusler Alloys.” 1910. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 23, 2020.
http://hdl.handle.net/2142/16433.
MLA Handbook (7th Edition):
Stephenson, Edward Beattie. “Magnetic Properties of Heusler Alloys.” 1910. Web. 23 Jan 2020.
Vancouver:
Stephenson EB. Magnetic Properties of Heusler Alloys. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 1910. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/2142/16433.
Council of Science Editors:
Stephenson EB. Magnetic Properties of Heusler Alloys. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 1910. Available from: http://hdl.handle.net/2142/16433
Nelson Mandela Metropolitan University
12.
Nyembe, Hlanganani Siphelele.
Corrosion resistance of nanocrystalline titanium zirconium nitride layers deposited on ZIRLO.
Degree: 2018, Nelson Mandela Metropolitan University
URL: http://hdl.handle.net/10948/34744
► Zirconium (Zr) alloys are used as nuclear fuel cladding in water-cooled nuclear reactors. Being in contact with steam, the Zr-alloy is oxidised and it absorbs…
(more)
▼ Zirconium (Zr) alloys are used as nuclear fuel cladding in water-cooled nuclear reactors. Being in contact with steam, the Zr-alloy is oxidised and it absorbs hydrogen. The hydrogen pickup in Zr-alloys induces embrittlement of the tubes due to hydride formation. In this study, effectiveness of corrosion resistant nanocrystalline titanium zirconium nitride (nc-TiZrN) coatings on the surface of a Zr-alloy for the reduction of corrosion and hydrogen pickup is investigated. The nc-TiZrN layers were deposited onto the surface of ZIRLO® using the cathodic arc vapour deposition (CAVD) technique. The influence of nc-TiZrN coatings on the corrosion performance of ZIRLO® was investigated under the following conditions: (a) In an oxygen atmosphere at various temperatures from 400 to 900 ℃ for 30 minutes, (b) for various exposure times from 6 – 24 hours with the temperature kept constant at 500 ℃ in a tube furnace, and (c) in pure steam for 30 days at 360 ℃ and 18.7 MPa in an autoclave. The corrosion properties of the nc-TiZrN coated ZIRLO were compared to uncoated ZIRLO for all experiments. Following corrosion testing, the TiZrN coatings and oxide layers were investigated by scanning and transmission electron microscopy and energy dispersive X-ray spectroscopy. The TiZrN coating had a thickness of ~3.8 μm with a small number of Ti-rich and Nb-rich inclusions. The coating exhibited a single phase solid solution of Ti0.42Zr0.58N with a NaCl-type crystal structure and columnar nanocrystals. These columnar nanocrystals showed a strong {111} preferred orientation and the {111} planes of the TiZrN crystals are oriented parallel to the (001) planes of α-ZIRLO grains with <001> direction perpendicular to the coating/ZIRLO interface. The corrosion testing at various temperatures from 400 to 900 ℃ for 30 minutes showed that the TiZrN coating oxidises slowly and retained its microstructure, composition and crystallinity up to 600 ℃. At higher temperatures above 600 ℃, the TiZrN layer completely oxidised to a non-protective TiZr-oxide layer and resulted in rapid corrosion of the underlying ZIRLO substrate. The rapid corrosion was not observed in the uncoated ZIRLO sample for all temperatures. The results of samples subjected to annealing treatment at 500 ℃ in an oxygen atmosphere at various times up to 24 hours revealed that the TiZrN layer oxidises faster than ZIRLO. This was confirmed by sub-cubic and sub-parabolic oxide growth kinetics observed in the uncoated ZIRLO which are slower than the parabolic kinetics of TiZrN coated samples. In all coated samples, the spallation was observed near the edges of the samples. The spallation was caused by rapid corrosion of the underlying ZIRLO substrate which resulted from the penetration of oxygen ions between the TiZrN coating and ZIRLO substrate along the edges of the samples. In pure steam for 30 days at 360 ℃, a complete loss of the TiZrN layer occurred but the results show that the coating might have delayed the corrosion of ZIRLO. In summary, corrosion resistance of nc-TiZrN coated ZIRLO…
Subjects/Keywords: Zirconium alloys; Titanium alloys; Nanocrystals; Nanotechnology
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APA (6th Edition):
Nyembe, H. S. (2018). Corrosion resistance of nanocrystalline titanium zirconium nitride layers deposited on ZIRLO. (Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/34744
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Nyembe, Hlanganani Siphelele. “Corrosion resistance of nanocrystalline titanium zirconium nitride layers deposited on ZIRLO.” 2018. Thesis, Nelson Mandela Metropolitan University. Accessed January 23, 2020.
http://hdl.handle.net/10948/34744.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nyembe, Hlanganani Siphelele. “Corrosion resistance of nanocrystalline titanium zirconium nitride layers deposited on ZIRLO.” 2018. Web. 23 Jan 2020.
Vancouver:
Nyembe HS. Corrosion resistance of nanocrystalline titanium zirconium nitride layers deposited on ZIRLO. [Internet] [Thesis]. Nelson Mandela Metropolitan University; 2018. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/10948/34744.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nyembe HS. Corrosion resistance of nanocrystalline titanium zirconium nitride layers deposited on ZIRLO. [Thesis]. Nelson Mandela Metropolitan University; 2018. Available from: http://hdl.handle.net/10948/34744
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Urbana-Champaign
13.
Wu, Yan.
Advanced experimental characterization of deformation mechanisms and temperature changes on novel alloys systems.
Degree: PhD, Mechanical Engineering, 2019, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/104757
► The human civilization continues to benefit from novel alloys systems ascribed to their unprecedented functionalities. Among many, shape memory alloys (SMAs) and high entropy alloys…
(more)
▼ The human civilization continues to benefit from novel
alloys systems ascribed to their unprecedented functionalities. Among many, shape memory
alloys (SMAs) and high entropy
alloys (HEAs) are presently of great research interest in material science and engineering community. Unlike conventional
alloys, the former exhibits astonishing recoverability from excessive deformation and the latter possesses exceptional strength and ductility extending to cryogenic temperatures. This work investigates the high temperature response and elastocaloric effect of SMAs and strain hardening behavior of HEAs using advanced experimental techniques, i.e. digital image correlation (DIC), optical microscopy, electron microscopy, etc.
In the first portion of this dissertation, the mechanical responses of the NiTiHf high temperature SMAs are investigated. This class of materials represent a significant advancement in extending the functionality of binary NiTi to elevated temperatures above 100 °C. Despite this potential, the previous results in the literature point to a disappointingly low transformation strains with addition of Hf. On the other hand, based on theoretical analysis using the lattice constants, the transformation strains should increase substantially with increase in Hf content. The present study addresses this discrepancy. Using DIC, the transformation strain is established with very careful strain measurements at small scales in both isobaric and isothermal experiments. Because of the heterogeneity of strain distributions, the results depend on the sub-region considered. By scrutinizing the alloy systems with Hf content in the range from 12.5 to 25 at.%, we show that the experimental transformation strains in NiTiHf indeed increase with increasing Hf to unprecedented strain levels near 20%.
In the second part of this dissertation, the elastocaloric (EC) effect of SMA is examined. The EC effect refers to the rapid cooling in SMAs during reverse transformation from martensite to austenite under adiabatic conditions. We present a very comprehensive study of the EC response far extending the existing literature by studying the effect of loading states (tension and compression), long-term cycling, strain localization, and deformation temperatures in several alloy systems including CuZnAl, NiTi, NiTiCu, Ni2FeGa and NiTiHf13.3. We found a substantial temperature change of 14.2 °C in CuZnAl, 18.2 °C in NiTi, 15.2 °C in NiTiCu, 13.5 °C in Ni2FeGa, and 6.95 °C in NiTiHf13.3 upon reverse transformation depending on the entropy change (as high as 60 J/kg K), the stress hysteresis, the inhomogeneity of the transformation and the number of superelastic cycles. A gradual deterioration of the EC effect in tension develops, while in compression the EC effect can be sustained much longer (in excess of 104 cycles). The Ni2FeGa SMAs possess an operational EC temperature window of nearly 200 °C, which is the widest among the chosen SMAs. With over one hundred experiments reported, the current study represents an authoritative summary of the…
Advisors/Committee Members: Sehitoglu, Huseyin (advisor), Sehitoglu, Huseyin (Committee Chair), Bellon, Pascal (committee member), Krogstad, Jessica (committee member), Ertekin, Elif (committee member).
Subjects/Keywords: Shape Memory Alloys; High Entropy Alloys
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APA ·
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APA (6th Edition):
Wu, Y. (2019). Advanced experimental characterization of deformation mechanisms and temperature changes on novel alloys systems. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/104757
Chicago Manual of Style (16th Edition):
Wu, Yan. “Advanced experimental characterization of deformation mechanisms and temperature changes on novel alloys systems.” 2019. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 23, 2020.
http://hdl.handle.net/2142/104757.
MLA Handbook (7th Edition):
Wu, Yan. “Advanced experimental characterization of deformation mechanisms and temperature changes on novel alloys systems.” 2019. Web. 23 Jan 2020.
Vancouver:
Wu Y. Advanced experimental characterization of deformation mechanisms and temperature changes on novel alloys systems. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2019. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/2142/104757.
Council of Science Editors:
Wu Y. Advanced experimental characterization of deformation mechanisms and temperature changes on novel alloys systems. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2019. Available from: http://hdl.handle.net/2142/104757
University of Utah
14.
Hackett, Kenneth Robert.
Phase constitution and mechanical properties of carbides in the Ta-C system.
Degree: MS;, Materials Science & Engineering;, 2009, University of Utah
URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1766/rec/883
► Carbides in the Ta-C system were prepared by hot-pressing mixed powders of TaC and Ta in C/Ta atomic ratios of TaCo.6, TaCo.7, TaCu.8, TaCo.9, and…
(more)
▼ Carbides in the Ta-C system were prepared by hot-pressing mixed powders of TaC and Ta in C/Ta atomic ratios of TaCo.6, TaCo.7, TaCu.8, TaCo.9, and TaCi.o at 1800 °C for 2 h. Rietveld analysis was performed on all compositions, and it was found that TaCo.6 was a mixture of 21% hexagonal close packed (HCP) a-Ta2C and 79% rhombohedral ^ - T a ^ - x , TaCo.7 was a mixture of 44.6% rhombohedral ^ - T a ^ - x and 55.4% face centered cubic (FCC) TaCy , TaCo.s and TaCo.9 were approximately 100% FCC TaCy , and TaC 1.0 was approximately 100% TaC. The TaC and TaCy compositions, produced were single phase with C/Ta ratios essentially the same as the starting nominal compositions and densities exceeding 96.5% of theoretical. Grain size decreased with increasing carbon deficiency from 1.0 to 0.8, with a corresponding increase in Vickers hardness from 13.5 to 20.0 GPa. The flexural strength, however, decreased from 650 to 500 MPa due to a decrease in fracture toughness from 5.3 to 3.8 MPaVm. Fracture toughness measured by single-edge-precracked-beam (SEPB) technique was exceptionally high (12.7 ± 0.7 MPaVm) for the a-Ta2C and ^ - T a ^ . x composition with a high weight percent of the ^ - T a ^ . x phase (~83 wt %). This disconnect between the change in hardness and strength indicates that the toughened compositions may exhibit R-curve behavior. Fracture surfaces were highly faceted with multiple cleavage crack planes and steps for TaCo.6 and TaCo.7. It is possible that the cleavage planes correspond to the stacking faults between the FCC and the HCP stacking layers within the stacking sequence ABABCACABCBC of the ^ - T a ^ . x phase bridge cracks in the crack wake with accompanying variations in local carbon concentrations fluctuating between TaCy and a-Ta2C.
Subjects/Keywords: Carbides; Tantalum alloys
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APA (6th Edition):
Hackett, K. R. (2009). Phase constitution and mechanical properties of carbides in the Ta-C system. (Masters Thesis). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1766/rec/883
Chicago Manual of Style (16th Edition):
Hackett, Kenneth Robert. “Phase constitution and mechanical properties of carbides in the Ta-C system.” 2009. Masters Thesis, University of Utah. Accessed January 23, 2020.
http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1766/rec/883.
MLA Handbook (7th Edition):
Hackett, Kenneth Robert. “Phase constitution and mechanical properties of carbides in the Ta-C system.” 2009. Web. 23 Jan 2020.
Vancouver:
Hackett KR. Phase constitution and mechanical properties of carbides in the Ta-C system. [Internet] [Masters thesis]. University of Utah; 2009. [cited 2020 Jan 23].
Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1766/rec/883.
Council of Science Editors:
Hackett KR. Phase constitution and mechanical properties of carbides in the Ta-C system. [Masters Thesis]. University of Utah; 2009. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd2/id/1766/rec/883
University of Alberta
15.
Han, Chunfen.
Electrodeposition of Pb-free, Sn-based Alloy Solder
Films.
Degree: PhD, Department of Chemical and Materials
Engineering, 2009, University of Alberta
URL: https://era.library.ualberta.ca/files/8w32r639w
► The dominant materials used for solders in electronic assemblies over the past 60 years have been Pb-Sn alloys. Increasing pressure from environmental and health authorities…
(more)
▼ The dominant materials used for solders in electronic
assemblies over the past 60 years have been Pb-Sn alloys.
Increasing pressure from environmental and health authorities has
stimulated the development of various Pb-free solders. Two of the
most promising replacements are eutectic Sn-Cu and Sn-Ag-Cu alloys
that are produced primarily by electrodeposition. During soldering
and solid state aging (storage or in service of the electronic
assemblies), interactions take place at the solder/substrate metal
interface and form intermetallic compounds (IMCs) which are crucial
for the reliability of the solder joints. Simple and "green"
Sn-citrate and Sn-Cu-citrate solutions have been developed and
optimized to electrodeposit eutectic and near eutectic Sn-Cu solder
films. Sn-citrate suspensions with Cu particles and Sn-Cu-citrate
suspensions with Ag nano-particles have also been developed and
optimized to allow for electrochemical composite deposition of
eutectic and near eutectic Sn-Cu and Sn-Ag-Cu solder films.
Different plating and post-plating conditions, including solution
concentration, current density, agitation, additives, and aging,
have been investigated by evaluating their effects on plating rate,
deposit composition and microstructure. Tri-ammonium citrate is
used as the only complexing agent for Sn, Sn-Cu, and Sn-Ag-Cu
deposition. Speciation diagram calculations, reduction potential
calculations, and polarization studies are conducted to study
Sn-citrate solution chemistry and the kinetics of Sn
electrodeposition. X-ray photoelectron spectroscopy (XPS) analysis
is used to identify the precipitates formed in Sn-citrate solutions
at low pH. Current-controlled and potential-controlled
electrochemical techniques, nucleation modeling, and surface
morphology characterization techniques are applied to study the
nucleation and film growth mechanism of Sn and Sn-Cu
electrodeposition from Sn-citrate and Sn-Cu-citrate solutions.
Reflow and aging tests for deposited Sn-Cu and Sn-Ag-Cu solder
films on Cu and Ni substrates are performed to study the
interactions between the solder and the substrate and the formation
and growth of IMCs at the solder/substrate interface, by
characterizing the microstructure of the IMCs and calculating
diffusion coefficients.
Subjects/Keywords: Pb-Sn alloys
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APA (6th Edition):
Han, C. (2009). Electrodeposition of Pb-free, Sn-based Alloy Solder
Films. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/8w32r639w
Chicago Manual of Style (16th Edition):
Han, Chunfen. “Electrodeposition of Pb-free, Sn-based Alloy Solder
Films.” 2009. Doctoral Dissertation, University of Alberta. Accessed January 23, 2020.
https://era.library.ualberta.ca/files/8w32r639w.
MLA Handbook (7th Edition):
Han, Chunfen. “Electrodeposition of Pb-free, Sn-based Alloy Solder
Films.” 2009. Web. 23 Jan 2020.
Vancouver:
Han C. Electrodeposition of Pb-free, Sn-based Alloy Solder
Films. [Internet] [Doctoral dissertation]. University of Alberta; 2009. [cited 2020 Jan 23].
Available from: https://era.library.ualberta.ca/files/8w32r639w.
Council of Science Editors:
Han C. Electrodeposition of Pb-free, Sn-based Alloy Solder
Films. [Doctoral Dissertation]. University of Alberta; 2009. Available from: https://era.library.ualberta.ca/files/8w32r639w
Texas A&M University
16.
Guiza-Arguello, Viviana R.
Evaluation of Biomimetic and Alloy-based Materials for Orthopedic Applications.
Degree: 2013, Texas A&M University
URL: http://hdl.handle.net/1969.1/151159
► The basic principle of tissue engineering is the combination of appropriate cells with biomaterials under conditions that promote and lead to tissue formation. A tissue…
(more)
▼ The basic principle of tissue engineering is the combination of appropriate cells with biomaterials under conditions that promote and lead to tissue formation. A tissue engineering scaffold is a material that supports cells for their growth, proliferation, and differentiation in the absence of native extracellular matrix (ECM). The ECM was originally thought to provide primarily a mechanical support for the cells, but through receptors on the surface of cells, the ECM takes part in promoting cell adhesion, migration, growth, differentiation, and apoptosis. Ideally, a tissue engineered scaffold should mimic both the form and function of native ECM. Additionally, like any other biomaterial for implantation, a tissue engineered scaffold should be biocompatible and not initiate tissue reactions or immune responses.
This work focuses on the evaluation of the biocompatibility of novel alloy-based materials for orthopedic applications. In addition, in the context of bone regeneration, it examines the influence of select native ECM constituents on mesenchymal stem cell (MSC) osteogenic differentiation in 3-D contexts. On the other hand, given the crucial role of vasculogenesis in cell nutrition in the scaffolds, ECM mimics found to support osteogenesis were further evaluated for endothelial cell adhesion and migration. For the hydrogel systems presented in this manuscript, poly(ethylene glycol) diacrylate (PEGDA) networks were selected as the base scaffold due to the broad tunability of their mechanical properties and their previous use in bone regeneration applications. In addition, pure PEGDA hydrogels do not intrinsically promote cell adhesion. Thus, cell interactions with PEGDA gels are initially isolated to the interactions supported by the proteins tethered to the scaffold.
This work attempts to contribute to the development of novel materials that provide biocompatibility and enhanced versatility in orthopedic applications. Moreover, in the context of bone regeneration, the use of selective ECM biomolecules in hybrid hydrogel scaffolds will aid in the understanding of MSC osteogenic responses to specific ECM constituents. Additionally, incorporation of ECM mimics that support both osteogenesis and vasculogenesis will provide a more controlled platform which will serve as a foundation for the fabrication of more efficient vascularized bone constructs.
Advisors/Committee Members: Hahn, Mariah (advisor), Grunlan, Melissa (committee member), Kao, Katy (committee member), Ugaz, Victor (committee member).
Subjects/Keywords: Extracellular Matrix; Alloys
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APA (6th Edition):
Guiza-Arguello, V. R. (2013). Evaluation of Biomimetic and Alloy-based Materials for Orthopedic Applications. (Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/151159
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Guiza-Arguello, Viviana R. “Evaluation of Biomimetic and Alloy-based Materials for Orthopedic Applications.” 2013. Thesis, Texas A&M University. Accessed January 23, 2020.
http://hdl.handle.net/1969.1/151159.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Guiza-Arguello, Viviana R. “Evaluation of Biomimetic and Alloy-based Materials for Orthopedic Applications.” 2013. Web. 23 Jan 2020.
Vancouver:
Guiza-Arguello VR. Evaluation of Biomimetic and Alloy-based Materials for Orthopedic Applications. [Internet] [Thesis]. Texas A&M University; 2013. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/1969.1/151159.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Guiza-Arguello VR. Evaluation of Biomimetic and Alloy-based Materials for Orthopedic Applications. [Thesis]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/151159
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Aberdeen
17.
Majchrowski, Tomasz P.
Chemical behaviour of a nuclear-grade magnesium alloy during storage.
Degree: PhD, 2015, University of Aberdeen
URL: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225908
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655668
► Magnox, a magnesium alloy, was specifically developed in early 1950s for use as a fuel cladding in the British first generation nuclear civilian reactors. Magnesium…
(more)
▼ Magnox, a magnesium alloy, was specifically developed in early 1950s for use as a fuel cladding in the British first generation nuclear civilian reactors. Magnesium metal demonstrates outstanding properties for use as a nuclear fuel cladding; however, it has an intrinsic ability to undergo oxidation. This introduces significant limitations during aqueous storage required prior to reprocessing of the spent fuel. A possibility exists for a failure of the dated reprocessing facilities, and therefore this may require for the spent fuel to be kept in the aqueous storage for an extended period of time. In a most extreme case, the corrosion of the fuel cladding may lead to a contamination of the storage facilities with hazardous radioactive fission species and corrosion products. A comprehensive study of chemical behaviour of the Magnox alloy may allow a deeper understanding of the reactivity of the cladding and lead to improvements in management of storage of spent Magnox fuel, thus preventing corrosion induced leakage of hazardous products. The understanding of chemistry of the Magnox alloy during storage may be improved by the development of a novel approach to study corrosion reactions. Infrared spectroscopy and Raman spectroscopy are widely used to study properties of surfaces. In addition, electron microscopy provides with information on the structure and physical appearance of materials. The results show clear evidence for reactivity of the alloy to be greatly influenced by changes induced by nature of cooling processes upon simulated discharge of spent Magnox fuel from a reactor. It is evident that the fast cooling process using water introduces the most deleterious change to the properties of the material. It is understood that presence of water provides with favourable conditions for oxidation of the metal to take place. Opposite effect is observed with slow cooling under an atmosphere of carbon dioxide gas. Further studies using X-ray diffraction suggest that crystallinity of the alloy is increased during simulated reactor exposure and phase segregation takes place during cooling. The latter appears to be dependent on the nature of the cooling process, and thus as a result different strains are applied. Through the studies it is shown that the pond conditions also contribute to control of the behaviour of the fuel cladding. A series of experiments demonstrated that sodium carbonate offers paramount corrosion protection when compared to sodium hydroxide. Systematic investigations allowed for a complete corrosion mechanism of the Magnox cladding to be drawn. It is demonstrated that the effects of present as well past conditions should be assessed and taken into consideration when establishing chemical behaviour of a material.
Subjects/Keywords: 540; Magnesium alloys
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APA ·
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CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Majchrowski, T. P. (2015). Chemical behaviour of a nuclear-grade magnesium alloy during storage. (Doctoral Dissertation). University of Aberdeen. Retrieved from http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225908 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655668
Chicago Manual of Style (16th Edition):
Majchrowski, Tomasz P. “Chemical behaviour of a nuclear-grade magnesium alloy during storage.” 2015. Doctoral Dissertation, University of Aberdeen. Accessed January 23, 2020.
http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225908 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655668.
MLA Handbook (7th Edition):
Majchrowski, Tomasz P. “Chemical behaviour of a nuclear-grade magnesium alloy during storage.” 2015. Web. 23 Jan 2020.
Vancouver:
Majchrowski TP. Chemical behaviour of a nuclear-grade magnesium alloy during storage. [Internet] [Doctoral dissertation]. University of Aberdeen; 2015. [cited 2020 Jan 23].
Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225908 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655668.
Council of Science Editors:
Majchrowski TP. Chemical behaviour of a nuclear-grade magnesium alloy during storage. [Doctoral Dissertation]. University of Aberdeen; 2015. Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225908 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655668
University of Hong Kong
18.
陈树阳; Chen, Shuyang.
Biological aspects of some novel Ti-based
alloys.
Degree: MSin Dental Materials, 2015, University of Hong Kong
URL: Chen,
S.
[陈树阳].
(2015).
Biological
aspects
of
some
novel
Ti-based
alloys.
(Thesis).
University
of
Hong
Kong,
Pokfulam,
Hong
Kong
SAR.
Retrieved
from
http://dx.doi.org/10.5353/th_b5573051
;
http://hdl.handle.net/10722/221008
published_or_final_version
Dental Materials Science
Master
Master of Science in Dental Materials
Science
Subjects/Keywords: Titanium alloys - Biocompatibility
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
陈树阳; Chen, S. (2015). Biological aspects of some novel Ti-based
alloys. (Masters Thesis). University of Hong Kong. Retrieved from Chen, S. [陈树阳]. (2015). Biological aspects of some novel Ti-based alloys. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5573051 ; http://hdl.handle.net/10722/221008
Chicago Manual of Style (16th Edition):
陈树阳; Chen, Shuyang. “Biological aspects of some novel Ti-based
alloys.” 2015. Masters Thesis, University of Hong Kong. Accessed January 23, 2020.
Chen, S. [陈树阳]. (2015). Biological aspects of some novel Ti-based alloys. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5573051 ; http://hdl.handle.net/10722/221008.
MLA Handbook (7th Edition):
陈树阳; Chen, Shuyang. “Biological aspects of some novel Ti-based
alloys.” 2015. Web. 23 Jan 2020.
Vancouver:
陈树阳; Chen S. Biological aspects of some novel Ti-based
alloys. [Internet] [Masters thesis]. University of Hong Kong; 2015. [cited 2020 Jan 23].
Available from: Chen, S. [陈树阳]. (2015). Biological aspects of some novel Ti-based alloys. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5573051 ; http://hdl.handle.net/10722/221008.
Council of Science Editors:
陈树阳; Chen S. Biological aspects of some novel Ti-based
alloys. [Masters Thesis]. University of Hong Kong; 2015. Available from: Chen, S. [陈树阳]. (2015). Biological aspects of some novel Ti-based alloys. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5573051 ; http://hdl.handle.net/10722/221008
19.
Rajan, Diwan Singh.
Corrosion characteristics of different metallic alloys in
acidic medium.
Degree: Chemistry, 2013, Shri Jagdishprasad Jhabarmal Tibarewala University
URL: http://shodhganga.inflibnet.ac.in/handle/10603/13916
► Corrosion is the disintegration or loss in useful properties of metal and their alloys or material of construction into its constituent atoms due to attack…
(more)
▼ Corrosion is the disintegration or loss in useful
properties of metal and their alloys or material of construction
into its constituent atoms due to attack of atmospheric gases
resulting in to chemical (dry corrosion) or electrochemical (wet
corrosion) reactions with its surroundings. Corrosion can also be
defined as an electrochemical process in which oxidation and
simultaneous reduction of metals takes place in a reaction in
presence of an oxidant such as oxygen. Dry and wet corrosion are
its two types. Formation of an oxides of metallic iron due to
oxidation in solid form is a well-known example of electrochemical
dry corrosion, commonly known as rusting. This type of loss of
material resulting in corrosion typically produces oxide(s) or
salt(s) of the original metal. Phenomenon of corrosion can not
avoided but losses due to corrosion can be minimized. Almost all
form of material corrodes in ways or other, such as ceramics
(concrete corrosion) or polymers, although in this context, the
term degradation is more commonly used. newlineCorrosion is also
defined as loss in the useful property of the material due to
attack of atmospheric gases. It can also be defined as the wearing
away (loss) of metals due to attack of atmospheric gases (air and
moisture) on the surface of metal and their alloys resulting in a
chemical or electrochemical reaction. newlineEffect of atmospheric
gases is different for different metallic alloys. Many structural
alloys corrodes severely while other mildly depending upon a number
of factors like humidity content, nature of pollutant, rate of flow
etc. The rate of corrosion can be strongly affected by exposure to
certain substances present in air. There are different forms of
corrosion. It can be concentrated locally to form a pit or crack,
or it can extended (spread) across a large area more or less
uniformly corroding the surface resulting in uniform type of
corrosion. Corrosion may be diffusion controlled process as it
occurs mainly on the exposed surfaces of material and their
alloys.
Summary p. 136-154, References p.
155-156
Advisors/Committee Members: Malik, Shiv Darshan.
Subjects/Keywords: Chemistry; Metallic alloys
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Rajan, D. S. (2013). Corrosion characteristics of different metallic alloys in
acidic medium. (Thesis). Shri Jagdishprasad Jhabarmal Tibarewala University. Retrieved from http://shodhganga.inflibnet.ac.in/handle/10603/13916
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Rajan, Diwan Singh. “Corrosion characteristics of different metallic alloys in
acidic medium.” 2013. Thesis, Shri Jagdishprasad Jhabarmal Tibarewala University. Accessed January 23, 2020.
http://shodhganga.inflibnet.ac.in/handle/10603/13916.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rajan, Diwan Singh. “Corrosion characteristics of different metallic alloys in
acidic medium.” 2013. Web. 23 Jan 2020.
Vancouver:
Rajan DS. Corrosion characteristics of different metallic alloys in
acidic medium. [Internet] [Thesis]. Shri Jagdishprasad Jhabarmal Tibarewala University; 2013. [cited 2020 Jan 23].
Available from: http://shodhganga.inflibnet.ac.in/handle/10603/13916.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rajan DS. Corrosion characteristics of different metallic alloys in
acidic medium. [Thesis]. Shri Jagdishprasad Jhabarmal Tibarewala University; 2013. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/13916
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Johannesburg
20.
Mochele, Julius Thabiso.
Magnetoelasticity of ternary Cr-Ru-Mo alloys.
Degree: 2012, University of Johannesburg
URL: http://hdl.handle.net/10210/7610
► M.Sc.
Alloying Cr with non-magnetic Ru, results in unusual magnetoelastic effects due to strong magnetic interactions with the lattice. In the low concentration region, Ru…
(more)
▼ M.Sc.
Alloying Cr with non-magnetic Ru, results in unusual magnetoelastic effects due to strong magnetic interactions with the lattice. In the low concentration region, Ru increases the Neél temperature TN due to the enhancement of the spin density wave (SDW). The temperature dependence of the thermal expansion coefficient (a) of Cr o.997Ru0.003 displays Invar behaviour within a small temperature region (7.-: 5 K) of the magnetic transition at TN 390 K). This alloy is of little practical use since the Invar behaviour is well above room temperature. Mo, which is isoelectronic with Cr, is known to vary the strength of the SDW in Cr without changing its basic nature. It reduces and broadens the magnetic transition at TN of Cr and its alloys. Therefore Mo seems to be suitable for tayloring the Cr 0.997R110.003 alloy system, reducing the temperature region, in which the Invar effects are observed, down to room temperature. The temperature dependence of the thermal expansion and of the elastic constants were measured for (Cr i _rMor )0.997Ruo.003 and (Cri _yMoy )0.995Ru0.005 in the temperature range between 77 K and 450 K so that the effects of Mo on the Invar behaviour of Cr 0.997Ru0.003 and on the magnetoelasticity in (Cr i„Moz )0.997Ru0.003 and (Cr i _yMoy )0.995Ru0.005 could be studied. From the Invar-study we learn that although the addition of Mo to Cro.997Rno.003 succesfully decreased the Neel temperature down to room temperature, it simultaneously increased the coefficient of thermal expansion to much larger values. We were therefore not successful in our effort to improve the Invar type properties of the Cr0.997R110.003 alloy by the addition of Mo. Although the study was mainly focussed on tayloring the antiferromagnetic Invar Cr o.997Ru0.003 alloy with Mo, we also theoretically analysed the effects on the magnetoelasticity of Cr0.997Ru0.003, in terms of the temperature dependences of the thermal expansion and elastic constants in (Cri_xMox)0.997Ruo.003 and (Cri— yMoy )o.99sRuo.00s alloy systems when some of Cr atoms are replaced by those of Mo. In both Cr-Ru-Mo alloy systems, a(T) showed well defined anomalies with a minimum at the commensurate (C) SDW to paramagnetic (P) phase transition at TN and a maximum in the incommensurate (I) SDW-CSDW transition at T IC for x < 0.015 and y = 0.01. For x > 0.015, the CSDW state is completely suppressed and only the ISDW-P phase transition at TN is observed. The temperature dependence of the elastic constants in (Cri,M0x)o.997Ruo.003 with x = 0.015 and 0.07 showed only the ISDW-P phase transition, while the alloy with x = 0.007 showed both the CSDW-P at TN and a very small ISDW-CSDW transition at Ti.c . In general: Mo decreases the magnetic contributions to the volume and to the bulk modulus of Cr0.997Ru0.003 below TN . Mo completely suppresses the CSDW state of Cr0.997R11 0.003. The (Cri„Mos )0.997Ruo .003 and (Cri _yMoy )0 .995Ru0.005 show a second order phase transition at TN . Hysteresis effects were observed in (Cri—xMox)o.997Ruo.003 at the ISDW-CSDW phase…
Subjects/Keywords: Ternary alloys; Magnetostriction
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APA ·
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CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Mochele, J. T. (2012). Magnetoelasticity of ternary Cr-Ru-Mo alloys. (Thesis). University of Johannesburg. Retrieved from http://hdl.handle.net/10210/7610
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Mochele, Julius Thabiso. “Magnetoelasticity of ternary Cr-Ru-Mo alloys.” 2012. Thesis, University of Johannesburg. Accessed January 23, 2020.
http://hdl.handle.net/10210/7610.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Mochele, Julius Thabiso. “Magnetoelasticity of ternary Cr-Ru-Mo alloys.” 2012. Web. 23 Jan 2020.
Vancouver:
Mochele JT. Magnetoelasticity of ternary Cr-Ru-Mo alloys. [Internet] [Thesis]. University of Johannesburg; 2012. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/10210/7610.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Mochele JT. Magnetoelasticity of ternary Cr-Ru-Mo alloys. [Thesis]. University of Johannesburg; 2012. Available from: http://hdl.handle.net/10210/7610
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Johannesburg
21.
Reddy, Leelakrishna.
Antiferromagnetic and quantum critical behaviour of the (Cr86Ru14)1–x(V,Mn)x alloy system.
Degree: 2011, University of Johannesburg
URL: http://hdl.handle.net/10210/3826
► M.Sc.
An experimental study on the magnetic properties of the (Cr86Ru14)1–x(V,Mn)x alloy system is reported in this thesis. The work focusses mainly on two aspects…
(more)
▼ M.Sc.
An experimental study on the magnetic properties of the (Cr86Ru14)1–x(V,Mn)x alloy system is reported in this thesis. The work focusses mainly on two aspects of the magnetic behaviour of this alloy system; firstly that of the base alloy Cr86Ru14 having a Ru concentration on the magnetic phase diagram of the Cr-Ru system that is close to a putative quantum critical point (QCP) (xc ≈ 17 at.% Ru), and secondly, of the effects of tuning this base alloy towards (V-addition) or away (Mn-addition) from the QCP. For the Cr86Ru14 base alloy, measurements of the electrical resistivity and elastic constants as functions of temperature and pressure are reported. These are supplemented by thermal expansion and neutron diffraction measurements as a function of temperature through the Néel transition temperature, TN.
Subjects/Keywords: Alloys - Magnetic properties
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Reddy, L. (2011). Antiferromagnetic and quantum critical behaviour of the (Cr86Ru14)1–x(V,Mn)x alloy system. (Thesis). University of Johannesburg. Retrieved from http://hdl.handle.net/10210/3826
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Reddy, Leelakrishna. “Antiferromagnetic and quantum critical behaviour of the (Cr86Ru14)1–x(V,Mn)x alloy system.” 2011. Thesis, University of Johannesburg. Accessed January 23, 2020.
http://hdl.handle.net/10210/3826.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Reddy, Leelakrishna. “Antiferromagnetic and quantum critical behaviour of the (Cr86Ru14)1–x(V,Mn)x alloy system.” 2011. Web. 23 Jan 2020.
Vancouver:
Reddy L. Antiferromagnetic and quantum critical behaviour of the (Cr86Ru14)1–x(V,Mn)x alloy system. [Internet] [Thesis]. University of Johannesburg; 2011. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/10210/3826.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Reddy L. Antiferromagnetic and quantum critical behaviour of the (Cr86Ru14)1–x(V,Mn)x alloy system. [Thesis]. University of Johannesburg; 2011. Available from: http://hdl.handle.net/10210/3826
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Hong Kong
22.
Lee, Wing-cheung.
Functional coatings on Ti-6A1-4V and NiTi shape memory
alloy for medical applications.
Degree: M. Phil., 2011, University of Hong Kong
URL: Lee,
W.
[李永祥].
(2011).
Functional
coatings
on
Ti-6A1-4V
and
NiTi
shape
memory
alloy
for
medical
applications.
(Thesis).
University
of
Hong
Kong,
Pokfulam,
Hong
Kong
SAR.
Retrieved
from
http://dx.doi.org/10.5353/th_b4715052
;
http://dx.doi.org/10.5353/th_b4715052
;
http://hdl.handle.net/10722/179970
► Due to its excellent biocompatibility and mechanical properties, Ti-6Al-4V alloy has been extensively used in the medical field, especially as a material for hard tissue…
(more)
▼ Due to its excellent biocompatibility and
mechanical properties, Ti-6Al-4V alloy has been extensively used in
the medical field, especially as a material for hard tissue
replacement. Owing to the unique shape memory and superelastic
properties, NiTi shape memory alloy (SMA, with 50.8 at.% of Ni) has
been investigated for load-bearing applications in orthopedics and
dentistry. Since the longevity of current metal implants is
approximately 10 to 15 years, many patients need to have revision
surgeries in their lifetime. Therefore, there is great interest in
the long-term stability, biocompatibility, bioactivity and other
properties of Ti-6Al-4V and NiTi SMA implants. Implant-associated
infections also pose serious threat to the success of metal
implants. The goal of this project was to investigate several
low-temperature surface modification techniques, including
anodization and electrochemical deposition, and formulate coatings
for potential clinical applications. Accordingly, several types of
coatings were synthesized on Ti-6Al-4V and NiTi SMA substrates.
Various aspects of the coatings, such as morphology, chemical
composition, crystallinity, phase and bioactivity, were analyzed.
Firstly, a systematic study on the formation of titania nanotubes
on Ti-6Al-4V by anodization was performed. Anodizing voltage and
time were varied for comparisons. A dense and compact titania
nanotube layer was synthesized on Ti-6Al-4V by anodizing at 25 V
for 20 min. The titania nanotubes formed were rutile. After
annealing at 500 °C for 1 h, the titania nanotubes became anatase.
The anatase phase exhibited better wettability than the rutile
phase. Secondly, dense and compact apatite coatings were formed on
NiTi SMA samples through electrochemical deposition using mainly
double-strength simulated body fluid (2SBF) as the electrolyte. The
deposition conditions were varied and apatite coating
characteristics studied. With the inclusion of collagen molecules
(0.1 mg/ml) in the electrolyte (2SBFC), apatite/collagen composite
coatings were fabricated. Collagen fibrils were not only observed
on the surface of composite coatings but also were embedded inside
in the coatings and at the coating-substrate interface. Results
obtained from transmission electron microscopic and X-ray
diffraction analyses showed that the apatite crystals in apatite
coatings and apatite/collagen composite coatings were
calcium-deficient carbonated hydroxyapatite. Apatite/collagen
composite coatings exhibited excellent hydrophilicity, whereas
apatite coatings displayed hydrophobic surfaces. Finally,
gentamicin-loaded, tobramycin-loaded, and vancomycin-loaded apatite
coatings and apatite/collagen composite coatings were synthesized
on NiTi SMA samples through electrochemical deposition using
different drug concentrations in the electrolytes. A comparative
study of apatite coatings and apatite/collagen composite coatings
as drug delivery vehicles were conducted. Different aspects of
antibiotic-loaded coatings (surface characteristics, chemical
composition, wettability,…
Subjects/Keywords: Nickel-titanium alloys.; Titanium alloys.; Coatings.; Shape memory alloys.
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lee, W. (2011). Functional coatings on Ti-6A1-4V and NiTi shape memory
alloy for medical applications. (Masters Thesis). University of Hong Kong. Retrieved from Lee, W. [李永祥]. (2011). Functional coatings on Ti-6A1-4V and NiTi shape memory alloy for medical applications. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4715052 ; http://dx.doi.org/10.5353/th_b4715052 ; http://hdl.handle.net/10722/179970
Chicago Manual of Style (16th Edition):
Lee, Wing-cheung. “Functional coatings on Ti-6A1-4V and NiTi shape memory
alloy for medical applications.” 2011. Masters Thesis, University of Hong Kong. Accessed January 23, 2020.
Lee, W. [李永祥]. (2011). Functional coatings on Ti-6A1-4V and NiTi shape memory alloy for medical applications. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4715052 ; http://dx.doi.org/10.5353/th_b4715052 ; http://hdl.handle.net/10722/179970.
MLA Handbook (7th Edition):
Lee, Wing-cheung. “Functional coatings on Ti-6A1-4V and NiTi shape memory
alloy for medical applications.” 2011. Web. 23 Jan 2020.
Vancouver:
Lee W. Functional coatings on Ti-6A1-4V and NiTi shape memory
alloy for medical applications. [Internet] [Masters thesis]. University of Hong Kong; 2011. [cited 2020 Jan 23].
Available from: Lee, W. [李永祥]. (2011). Functional coatings on Ti-6A1-4V and NiTi shape memory alloy for medical applications. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4715052 ; http://dx.doi.org/10.5353/th_b4715052 ; http://hdl.handle.net/10722/179970.
Council of Science Editors:
Lee W. Functional coatings on Ti-6A1-4V and NiTi shape memory
alloy for medical applications. [Masters Thesis]. University of Hong Kong; 2011. Available from: Lee, W. [李永祥]. (2011). Functional coatings on Ti-6A1-4V and NiTi shape memory alloy for medical applications. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4715052 ; http://dx.doi.org/10.5353/th_b4715052 ; http://hdl.handle.net/10722/179970
23.
Rahman, A. H. M. Esfakur.
Transient Liquid Phase Bonding of Titanium-, Iron- and Nickel- Based Alloys.
Degree: PhD, Mechanical Engineering, 2013, University of North Dakota
URL: https://commons.und.edu/theses/885
► The operating temperature of land-based gas turbines and jet engines are ever-increasing to increase the efficiency, decrease the emissions and minimize the cost. Within…
(more)
▼ The operating temperature of land-based gas turbines and jet engines are ever-increasing to increase the efficiency, decrease the emissions and minimize the cost. Within the engines, complex-shaped parts experience extreme temperature, fatigue and corrosion conditions. Ti-based, Ni-based and Fe-based
alloys are commonly used in gas turbines and jet engines depending on the temperatures of different sections. Although those
alloys have superior mechanical, high temperature and corrosion properties, severe operating conditions cause fast degradation and failure of the components. Repair of these components could reduce lifecycle costs. Unfortunately, conventional fusion welding is not very attractive, because Ti reacts very easily with oxygen and nitrogen at high temperatures, Ni-based superalloys show heat affected zone (HAZ) cracking, and stainless steels show intergranular corrosion and knife-line attack. On the other hand, transient liquid phase (TLP) bonding method has been considered as preferred joining method for those types of
alloys.
During the initial phase of the current work commercially pure Ti, Fe and Ni were diffusion bonded using commercially available interlayer materials. Commercially pure Ti (Ti-grade 2) has been diffusion bonded using silver and copper interlayers and without any interlayer. With a silver (Ag) interlayer, different intermetallics (AgTi, AgTh) appeared in the joint centerline microstructure. While with a Cu interlayer eutectic mixtures and Ti-Cu solid solutions appeared in the joint centerline. The maximum tensile strengths achieved were 160 MPa, 502 MPa, and 3 82 MP a when Ag, Cu and no interlayers were used, respectively. Commercially pure Fe ( cp-F e) was diffusion bonded using Cu (25 m) and Au-12Ge eutectic interlayer (100 μm). Cu diffused predominantly along austenite grain boundaries in all bonding conditions. Residual interlayers appeared at lower bonding temperature and time, however, voids were observed in the joint centerline at higher joining temperature and time. Dispersed Au-rich particles were observed in the base metal near interface. The highest ultimate tensile strengths obtained for the bonded Fe were 291±2 MPa using a Cu interlayer at 1030°C for 10 hand 315±4 MPa using a Au-12Ge interlayer at 950°C for 15 h. Commercially pure Ni (cp-Ni) was diffusion bonded using a Al, Au-12Ge or Cu interlayer. The formation of intermetallics could not be avoided when Al interlayer was used. Even though no intermetallics were obtained with Au-12Ge or Cu interlayer, appreciable strength of the joint was not found.
Next, the simple bonding systems were modeled numerically. It is hoped that the simple models can be extended for higher order
alloys. The modeling of TLP joint means to come up with a mathematical model which can predict the concentration profiles of diffusing species. The concentration dependence of diffusivity in a multi-component diffusion system makes it complicated to predict the concentration profiles of diffusing species. The so-called chemical…
Advisors/Committee Members: Dr. Matthew N. Cavalli.
Subjects/Keywords: Diffusion bonding; titanium alloys; iron alloys; nickel alloys; Engineering
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APA (6th Edition):
Rahman, A. H. M. E. (2013). Transient Liquid Phase Bonding of Titanium-, Iron- and Nickel- Based Alloys. (Doctoral Dissertation). University of North Dakota. Retrieved from https://commons.und.edu/theses/885
Chicago Manual of Style (16th Edition):
Rahman, A H M Esfakur. “Transient Liquid Phase Bonding of Titanium-, Iron- and Nickel- Based Alloys.” 2013. Doctoral Dissertation, University of North Dakota. Accessed January 23, 2020.
https://commons.und.edu/theses/885.
MLA Handbook (7th Edition):
Rahman, A H M Esfakur. “Transient Liquid Phase Bonding of Titanium-, Iron- and Nickel- Based Alloys.” 2013. Web. 23 Jan 2020.
Vancouver:
Rahman AHME. Transient Liquid Phase Bonding of Titanium-, Iron- and Nickel- Based Alloys. [Internet] [Doctoral dissertation]. University of North Dakota; 2013. [cited 2020 Jan 23].
Available from: https://commons.und.edu/theses/885.
Council of Science Editors:
Rahman AHME. Transient Liquid Phase Bonding of Titanium-, Iron- and Nickel- Based Alloys. [Doctoral Dissertation]. University of North Dakota; 2013. Available from: https://commons.und.edu/theses/885
Indian Institute of Science
24.
Abdul Azeem, Mohd.
Microstructure And Texture Evolution And Its Effect On Mechanical Properties In Dilute Magnesium Based AZ21 Alloy.
Degree: 2006, Indian Institute of Science
URL: http://hdl.handle.net/2005/408
► Dilute Mg alloys are exclusively identified for wrought structural applications in automotive industry. Any improvement in mechanical properties of alloys is possible only by grain…
(more)
▼ Dilute Mg
alloys are exclusively identified for wrought structural applications in automotive industry. Any improvement in mechanical properties of
alloys is possible only by grain size refinement and by the development of suitable texture. The grain size, grain size anisotropy and texture in these
alloys affect the compatibility stresses in a very complex manner. To launch a full scale study towards understanding the complex deformation mechanisms operating in these
alloys, it is necessary to understand the effect of grain size and texture on the mechanical behavior of Mg
alloys in a broad or semi-quantitative manner first. Current literature lacks such broad study. In this present study, the effect of grain size, grain size anisotropy and texture evolution on the mechanical properties are examined in order to develop an understanding of the deformation mechanism that control the mechanical properties of a dilute conventionally extruded Mg alloy, AZ21.
The approach adopted was to first study the microstructure and texture evolution in this conventionally extruded alloy. Since the grain sizes in these
alloys vary over a wide range, it is hence necessary to study the microstructure evolution in a highly quantitative manner. In understanding texture, the present study is only limited to qualitatively evaluating the evolution of fibre component of texture using X-Ray Diffraction spectra.
For truly quantitative microstructure evolution results in materials were grains sizes are spread over a wide range, it is critical to study a statistically enough no. of grains. Hence to avoid any sampling error, large montages (about 0.3 sq. mm) were constructed out of a series of high resolution images captured using an optical microscope. The montages so constructed are subjected to extensive image enhancement and various other operations are performed to convert these coloured to binary montages. Information like grain size, diameter etc., can be easily extracted from these binary montages and used for further analysis.
Fibre texture in these conventionally extruded dilute Mg
alloys generally develops due to alignment of basal planes along the direction of extrusion. The Critical Resolved Shear Stress for basal slip is very low when compared to that of non-basal planes. And also since there are very limited primary slip systems in these dilute Mg
alloys, the development of strong fibre texture drastically changes the compatibility stresses and hence the mechanical properties .
To broadly study the effect of microstructure-texture on mechanical proerties, after post extrusion annealing, heat treatments representing typical microstructure-texture combinations were identified. Effect of each microstructure-texture combination on the tensile and completely reversed cyclic fatigue properties are studied and qualitatively interpreted.
The fibre texture showed pronounced effect on tensile ductility but it hardly affected the yield strength. With just 10% reduction in BPI, the ductility reduced by about 50%. A small change in…
Advisors/Committee Members: Ramamurty, U.
Subjects/Keywords: Magnesium Alloys; Annealing; Recrystallization; Magnesium Alloys - Mechanical Properties; Magnesium Alloys - Deformation; Magnesium Alloys - Microstructure Evolution; AZ21; Fibre Texture; Mg Alloys; Metallurgy
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APA ·
Chicago ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Abdul Azeem, M. (2006). Microstructure And Texture Evolution And Its Effect On Mechanical Properties In Dilute Magnesium Based AZ21 Alloy. (Thesis). Indian Institute of Science. Retrieved from http://hdl.handle.net/2005/408
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Abdul Azeem, Mohd. “Microstructure And Texture Evolution And Its Effect On Mechanical Properties In Dilute Magnesium Based AZ21 Alloy.” 2006. Thesis, Indian Institute of Science. Accessed January 23, 2020.
http://hdl.handle.net/2005/408.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Abdul Azeem, Mohd. “Microstructure And Texture Evolution And Its Effect On Mechanical Properties In Dilute Magnesium Based AZ21 Alloy.” 2006. Web. 23 Jan 2020.
Vancouver:
Abdul Azeem M. Microstructure And Texture Evolution And Its Effect On Mechanical Properties In Dilute Magnesium Based AZ21 Alloy. [Internet] [Thesis]. Indian Institute of Science; 2006. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/2005/408.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Abdul Azeem M. Microstructure And Texture Evolution And Its Effect On Mechanical Properties In Dilute Magnesium Based AZ21 Alloy. [Thesis]. Indian Institute of Science; 2006. Available from: http://hdl.handle.net/2005/408
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Indian Institute of Science
25.
Sen, Indrani.
Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys.
Degree: 2010, Indian Institute of Science
URL: http://hdl.handle.net/2005/1430
► Titanium alloys are important engineering alloys that are extensively used in various industries. This is due to their unique combination of mechanical and physical properties…
(more)
▼ Titanium
alloys are important engineering
alloys that are extensively used in various industries. This is due to their unique combination of mechanical and physical properties such as low density combined with high strength and toughness as well as outstanding corrosion resistance. An additional benefit associated with Ti
alloys, in general, is that their properties are relatively temperature-insensitive between cryogenic temperature and ~500 °C. Amongst the Ti
alloys, Ti-6Al-4V (referred as Ti64) is a widely used alloy. Conventionally cast Ti64 possesses classical Widmanstätten microstructure of (hcp) α and (bcc) β phases. However this microstructure suffers from large prior β grain size, which tends be in the order of a few mm. Such large grain sizes are associated with poor processability as well as inferior mechanical performance. The necessity to break this coarse as-cast microstructure down, through several successive thermo-mechanical processing steps, adds considerably to the cost of finished Ti alloy products, making them expensive vis-à-vis other competing
alloys.
The addition of small amount of B (~0.1%) to Ti64
alloys, on the other hand reduces the cast grain size from couple of mm to ~200 µm. Moreover, addition of B to Ti
alloys produces the intermetallic TiB needles during solidification by an in situ chemical reaction. The overall objective of this work is to gain insights into the role of microstructural modifications, induced by B addition to Ti64, on the mechanical performance of the
alloys, in particular the room temperature damage tolerance (fracture toughness and fatigue crack growth) characteristics. The key questions we seek to answer through this study are the following: (a) What role does the microstructural refinement plays on the quasistatic as well as fracture and fatigue behavior and high temperature deformability of the
alloys? (c) A hierarchy of microstructural length scales exist in Ti
alloys. These are the lath, colony and grain sizes. Which of these microstructural parameters control the mechanical performance of the alloy? (b) What (possibly detrimental) role, if any, do the TiB needles play in influencing the mechanical performance of Ti64
alloys? This is because TiB being much stiffer, strain incompatibility between the matrix and the TiB phase could lead to easy nucleation of cracks during cyclic loading as well as can pose problems during dynamic deformation. (d) What is the optimum amount of B that can be added to Ti64 such that the most desirable combination of properties can be achieved?
Five B-modified Ti64
alloys with B content varying from 0.0 to 0.55 wt.% were utilised to answer the above questions. Marked prior β grain size reduction was noted with up to 0.1 wt.% B addition. Simultaneous refinement of α/β colony size has also been observed. The addition of B to Ti64, on the other hand increases the α lath size. The TiB needles that form in-situ during casting are arranged in a necklace like structure surrounding the grain boundaries for higher B added Ti64
alloys.
An…
Advisors/Committee Members: Ramamurty, U.
Subjects/Keywords: Titanium Alloys - Mechanical Properties; Titanium Alloys - Fatigue; Titanium Alloys - Aerospace Applications; Titaniuim Alloys - Deformation; Titanium Alloys - Microstructure; Titanium Alloys - Tensile Behavior; Fracture Mechanics; Ti Alloys; Metallurgy
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sen, I. (2010). Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys. (Thesis). Indian Institute of Science. Retrieved from http://hdl.handle.net/2005/1430
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sen, Indrani. “Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys.” 2010. Thesis, Indian Institute of Science. Accessed January 23, 2020.
http://hdl.handle.net/2005/1430.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sen, Indrani. “Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys.” 2010. Web. 23 Jan 2020.
Vancouver:
Sen I. Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys. [Internet] [Thesis]. Indian Institute of Science; 2010. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/2005/1430.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sen I. Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys. [Thesis]. Indian Institute of Science; 2010. Available from: http://hdl.handle.net/2005/1430
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Indian Institute of Science
26.
Sen, Indrani.
Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys.
Degree: 2010, Indian Institute of Science
URL: http://etd.iisc.ernet.in/handle/2005/1430
;
http://etd.ncsi.iisc.ernet.in/abstracts/1844/G23638-Abs.pdf
► Titanium alloys are important engineering alloys that are extensively used in various industries. This is due to their unique combination of mechanical and physical properties…
(more)
▼ Titanium
alloys are important engineering
alloys that are extensively used in various industries. This is due to their unique combination of mechanical and physical properties such as low density combined with high strength and toughness as well as outstanding corrosion resistance. An additional benefit associated with Ti
alloys, in general, is that their properties are relatively temperature-insensitive between cryogenic temperature and ~500 °C. Amongst the Ti
alloys, Ti-6Al-4V (referred as Ti64) is a widely used alloy. Conventionally cast Ti64 possesses classical Widmanstätten microstructure of (hcp) α and (bcc) β phases. However this microstructure suffers from large prior β grain size, which tends be in the order of a few mm. Such large grain sizes are associated with poor processability as well as inferior mechanical performance. The necessity to break this coarse as-cast microstructure down, through several successive thermo-mechanical processing steps, adds considerably to the cost of finished Ti alloy products, making them expensive vis-à-vis other competing
alloys.
The addition of small amount of B (~0.1%) to Ti64
alloys, on the other hand reduces the cast grain size from couple of mm to ~200 µm. Moreover, addition of B to Ti
alloys produces the intermetallic TiB needles during solidification by an in situ chemical reaction. The overall objective of this work is to gain insights into the role of microstructural modifications, induced by B addition to Ti64, on the mechanical performance of the
alloys, in particular the room temperature damage tolerance (fracture toughness and fatigue crack growth) characteristics. The key questions we seek to answer through this study are the following: (a) What role does the microstructural refinement plays on the quasistatic as well as fracture and fatigue behavior and high temperature deformability of the
alloys? (c) A hierarchy of microstructural length scales exist in Ti
alloys. These are the lath, colony and grain sizes. Which of these microstructural parameters control the mechanical performance of the alloy? (b) What (possibly detrimental) role, if any, do the TiB needles play in influencing the mechanical performance of Ti64
alloys? This is because TiB being much stiffer, strain incompatibility between the matrix and the TiB phase could lead to easy nucleation of cracks during cyclic loading as well as can pose problems during dynamic deformation. (d) What is the optimum amount of B that can be added to Ti64 such that the most desirable combination of properties can be achieved?
Five B-modified Ti64
alloys with B content varying from 0.0 to 0.55 wt.% were utilised to answer the above questions. Marked prior β grain size reduction was noted with up to 0.1 wt.% B addition. Simultaneous refinement of α/β colony size has also been observed. The addition of B to Ti64, on the other hand increases the α lath size. The TiB needles that form in-situ during casting are arranged in a necklace like structure surrounding the grain boundaries for higher B added Ti64
alloys.
An…
Advisors/Committee Members: Ramamurty, U.
Subjects/Keywords: Titanium Alloys - Mechanical Properties; Titanium Alloys - Fatigue; Titanium Alloys - Aerospace Applications; Titaniuim Alloys - Deformation; Titanium Alloys - Microstructure; Titanium Alloys - Tensile Behavior; Fracture Mechanics; Ti Alloys; Metallurgy
Record Details
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Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sen, I. (2010). Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys. (Thesis). Indian Institute of Science. Retrieved from http://etd.iisc.ernet.in/handle/2005/1430 ; http://etd.ncsi.iisc.ernet.in/abstracts/1844/G23638-Abs.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sen, Indrani. “Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys.” 2010. Thesis, Indian Institute of Science. Accessed January 23, 2020.
http://etd.iisc.ernet.in/handle/2005/1430 ; http://etd.ncsi.iisc.ernet.in/abstracts/1844/G23638-Abs.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sen, Indrani. “Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys.” 2010. Web. 23 Jan 2020.
Vancouver:
Sen I. Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys. [Internet] [Thesis]. Indian Institute of Science; 2010. [cited 2020 Jan 23].
Available from: http://etd.iisc.ernet.in/handle/2005/1430 ; http://etd.ncsi.iisc.ernet.in/abstracts/1844/G23638-Abs.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sen I. Mechanical Behavior Of B-Modified Ti-6Al-4V Alloys. [Thesis]. Indian Institute of Science; 2010. Available from: http://etd.iisc.ernet.in/handle/2005/1430 ; http://etd.ncsi.iisc.ernet.in/abstracts/1844/G23638-Abs.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Indian Institute of Science
27.
Narayanan, P Ramesh.
A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications.
Degree: 2010, Indian Institute of Science
URL: http://hdl.handle.net/2005/1999
► Aluminium alloys, which are the most widely used materials in the aircraft and aerospace industries, find their applications due to high strength–to-density ratio, resistance to…
(more)
▼ Aluminium
alloys, which are the most widely used materials in the aircraft and aerospace industries, find their applications due to high strength–to-density ratio, resistance to catastrophic fracture, high degree of toughness, fabricability including good weldability and availability. High strength aluminum
alloys are used in different forms like sheets, forgings and extruded rods, welded and machined components in the aerospace industry. One major application of the aluminium
alloys in the space sector is in the launch vehicle and satellite sub-systems. The Indian Space Research Organization has met major challenges of indigenization of suitable aluminium
alloys, for example, Al-Cu
alloys (like AA2219) and Al–Zn-Mg
alloys (like AA7075 and AFNOR 7020).
Many failures of the metallic sub-systems made of different grades of aluminum
alloys have confirmed that high levels of residual stresses and unacceptable microstructures have played a role. Crystallographic texture in these materials has a very significant role to play in the performance of these materials in service. The anisotropy in the mechanical properties caused by crystallographic texture would add to the woes of the existing problems of residual stresses and directionality in the microstructure. In this context, a detailed study of crystallographic texture and residual stresses of high strength aluminium
alloys is mandatory. It is also important to study the influence of texture on the anisotropy in mechanical properties. The present research programme aims at addressing some of these aspects.
The entire work has been divided in three major sections, namely macro and micro texture analysis, non-destructive measurement of residual stresses using X-ray Diffraction (XRD) and the Ultrasonic Testing (UST) and the study of anisotropy in the mechanical properties arising due to the above two factors. The thesis composition is as follows.
In Chapter I, a detailed survey of the literature has been presented wherein basic physical metallurgy for different aluminum
alloys of interest has been given. Thereafter, details of texture measurement by the X-ray diffraction and Electron Back Scatter Diffraction (EBSD) are presented. This is followed by a detailed review on the texture studies carried out in aluminium
alloys under various conditions. Literature review on the two non-destructive methods, namely the X-ray diffraction and ultrasonic method has been carried out in detail. In order to account for microstructural changes, Differential Scanning Calorimetry (DSC) was carried out. Recent work on the mechanical property anisotropy arising due to high degree of mechanical working in aluminium
alloys has been reviewed.
Chapter II includes the experimental details involved in the course of the present investigation. The procedural details of cold rolling and associated microstructural changes are given in this chapter. This is followed by the texture measurement methods. Experimental details of the bulk texture measurement using the X-ray diffraction and micro texture…
Advisors/Committee Members: Ranganathan, S, Suwas, Satyam.
Subjects/Keywords: Aluminium Alloys; Crystallography; Aluminium Alloys - Mechanical Properties; Aluminium Alloys - Residual Stresses; Aluminium Alloys - Texture; Aluminium Alloys - Physical Metallurgy; Alluminium Alloys - Space Applications; Aluminium Alloys - Crystallographic Structure; AA2219 Al Alloy; AFNOR7020 Al Alloy; Al-Zn-Mg Alloys; Al Alloys; AA2219 Aluminium Alloys; Metallurgy
Record Details
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Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Narayanan, P. R. (2010). A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications. (Thesis). Indian Institute of Science. Retrieved from http://hdl.handle.net/2005/1999
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Narayanan, P Ramesh. “A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications.” 2010. Thesis, Indian Institute of Science. Accessed January 23, 2020.
http://hdl.handle.net/2005/1999.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Narayanan, P Ramesh. “A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications.” 2010. Web. 23 Jan 2020.
Vancouver:
Narayanan PR. A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications. [Internet] [Thesis]. Indian Institute of Science; 2010. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/2005/1999.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Narayanan PR. A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications. [Thesis]. Indian Institute of Science; 2010. Available from: http://hdl.handle.net/2005/1999
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Indian Institute of Science
28.
Narayanan, P Ramesh.
A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications.
Degree: 2010, Indian Institute of Science
URL: http://etd.iisc.ernet.in/handle/2005/1999
;
http://etd.ncsi.iisc.ernet.in/abstracts/2588/G24469-Abs.pdf
► Aluminium alloys, which are the most widely used materials in the aircraft and aerospace industries, find their applications due to high strength–to-density ratio, resistance to…
(more)
▼ Aluminium
alloys, which are the most widely used materials in the aircraft and aerospace industries, find their applications due to high strength–to-density ratio, resistance to catastrophic fracture, high degree of toughness, fabricability including good weldability and availability. High strength aluminum
alloys are used in different forms like sheets, forgings and extruded rods, welded and machined components in the aerospace industry. One major application of the aluminium
alloys in the space sector is in the launch vehicle and satellite sub-systems. The Indian Space Research Organization has met major challenges of indigenization of suitable aluminium
alloys, for example, Al-Cu
alloys (like AA2219) and Al–Zn-Mg
alloys (like AA7075 and AFNOR 7020).
Many failures of the metallic sub-systems made of different grades of aluminum
alloys have confirmed that high levels of residual stresses and unacceptable microstructures have played a role. Crystallographic texture in these materials has a very significant role to play in the performance of these materials in service. The anisotropy in the mechanical properties caused by crystallographic texture would add to the woes of the existing problems of residual stresses and directionality in the microstructure. In this context, a detailed study of crystallographic texture and residual stresses of high strength aluminium
alloys is mandatory. It is also important to study the influence of texture on the anisotropy in mechanical properties. The present research programme aims at addressing some of these aspects.
The entire work has been divided in three major sections, namely macro and micro texture analysis, non-destructive measurement of residual stresses using X-ray Diffraction (XRD) and the Ultrasonic Testing (UST) and the study of anisotropy in the mechanical properties arising due to the above two factors. The thesis composition is as follows.
In Chapter I, a detailed survey of the literature has been presented wherein basic physical metallurgy for different aluminum
alloys of interest has been given. Thereafter, details of texture measurement by the X-ray diffraction and Electron Back Scatter Diffraction (EBSD) are presented. This is followed by a detailed review on the texture studies carried out in aluminium
alloys under various conditions. Literature review on the two non-destructive methods, namely the X-ray diffraction and ultrasonic method has been carried out in detail. In order to account for microstructural changes, Differential Scanning Calorimetry (DSC) was carried out. Recent work on the mechanical property anisotropy arising due to high degree of mechanical working in aluminium
alloys has been reviewed.
Chapter II includes the experimental details involved in the course of the present investigation. The procedural details of cold rolling and associated microstructural changes are given in this chapter. This is followed by the texture measurement methods. Experimental details of the bulk texture measurement using the X-ray diffraction and micro texture…
Advisors/Committee Members: Ranganathan, S, Suwas, Satyam.
Subjects/Keywords: Aluminium Alloys; Crystallography; Aluminium Alloys - Mechanical Properties; Aluminium Alloys - Residual Stresses; Aluminium Alloys - Texture; Aluminium Alloys - Physical Metallurgy; Alluminium Alloys - Space Applications; Aluminium Alloys - Crystallographic Structure; AA2219 Al Alloy; AFNOR7020 Al Alloy; Al-Zn-Mg Alloys; Al Alloys; AA2219 Aluminium Alloys; Metallurgy
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APA ·
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APA (6th Edition):
Narayanan, P. R. (2010). A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications. (Thesis). Indian Institute of Science. Retrieved from http://etd.iisc.ernet.in/handle/2005/1999 ; http://etd.ncsi.iisc.ernet.in/abstracts/2588/G24469-Abs.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Narayanan, P Ramesh. “A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications.” 2010. Thesis, Indian Institute of Science. Accessed January 23, 2020.
http://etd.iisc.ernet.in/handle/2005/1999 ; http://etd.ncsi.iisc.ernet.in/abstracts/2588/G24469-Abs.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Narayanan, P Ramesh. “A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications.” 2010. Web. 23 Jan 2020.
Vancouver:
Narayanan PR. A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications. [Internet] [Thesis]. Indian Institute of Science; 2010. [cited 2020 Jan 23].
Available from: http://etd.iisc.ernet.in/handle/2005/1999 ; http://etd.ncsi.iisc.ernet.in/abstracts/2588/G24469-Abs.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Narayanan PR. A Study Of Crystallographic Texture, Residual Stresses And Mechanical Property Anisotropy In Aluminium Alloys For Space Applications. [Thesis]. Indian Institute of Science; 2010. Available from: http://etd.iisc.ernet.in/handle/2005/1999 ; http://etd.ncsi.iisc.ernet.in/abstracts/2588/G24469-Abs.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Indian Institute of Science
29.
Radhakrishnan, Madhavan.
Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys.
Degree: 2013, Indian Institute of Science
URL: http://etd.iisc.ernet.in/handle/2005/2623
;
http://etd.ncsi.iisc.ernet.in/abstracts/3400/G26264-Abs.pdf
► Plastic deformation of metals and alloys are invariably accompanied by the development of texture. The origin of texture is attributed to the deformation micro-mechanisms associated…
(more)
▼ Plastic deformation of metals and
alloys are invariably accompanied by the development of texture. The origin of texture is attributed to the deformation micro-mechanisms associated with processing. The face-centered cubic (FCC) metals and
alloys are known to exhibit two distinct types of textures when subjected to large strain rolling deformation, namely, (i) Cu-type texture, commonly seen in high/medium stacking fault energy (SFE) materials, (ii) Bs-type texture in low SFE materials. The circumstances that could result in the formation of Bs-type texture in low SFE materials still remains an open question and no definite mechanism has been uniquely agreed upon.
Apart from the SFE, grain size could also influence the deformation mechanism and hence the deformation texture. It is well known that in materials with grain sizes less than 100 nm (referred to as nano-crystalline materials), the microstructures contain large fraction of grain boundaries. This subsequently introduces a variety of deformation mechanisms in the microstructure involving grain boundary-mediated processes such as grain boundary sliding and grain rotation, in addition to slip and twinning. A clear understanding of texture evolution in nano-crystalline materials, particularly at large strains, is a topic that remains largely unexplored.
The present work is an attempt to address the aforementioned issues pertaining to the evolution of deformation texture, namely, (i) the effect of SFE and (ii) the effect of grain size, in FCC metals and
alloys. Nickel-cobalt
alloys are chosen as the model system for the present investigation. The addition of cobalt to nickel leads to a systematic reduction of SFE as a function of cobalt content. In this thesis, three
alloys of Ni-Co system have been considered, namely, nickel – 20 wt.% cobalt, nickel – 40 wt.% cobalt and nickel – 60 wt.% cobalt. For a comparison, pure nickel has also been subjected to similar study.
Chapter 1 of the thesis presents a detailed survey of literature pertaining to the evolution of rolling textures in FCC metals and
alloys, and chapter 2 includes the details of the experimental techniques and characterization procedures, which are commonly employed for the entire work.
Chapter 3 addresses the effect of stacking fault energy on the evolution of rolling texture. The materials subjected to study in this chapter are microcrystalline Ni-Co
alloys. The texture evolution in Ni-20Co is very similar to pure Ni, and a characteristic Cu-type rolling texture is observed. The evolution of texture in these materials is primarily attributed to the intense dislocation activity throughout the deformation stages. In Ni-40Co, a medium SFE material, the rolling texture was predominantly Cu-type up to a strain of ε = 3 (95% thickness reduction). However, beyond this strain level, namely at ε = 4 (98%), the texture gets transformed to Bs-type with orientations maxima predominantly close to Goss ({110} <001>) position. Simultaneously, the Cu component which was dominant until 95% reduction has…
Advisors/Committee Members: Suwas, Satyam.
Subjects/Keywords: Microcrystalline Nickel-Cobalt Alloys; Nanocrystalline Nickel-Cobalt Alloys; Face Centered Cubic (FCC) Metals and Alloys; Nanocrystalline Nickel Alloys; Microcrystalline Nickel Alloys; Microcrystalline Alloys; Polycrystalline Metals; Stacking Fault Energy Alloys; Crystalline Texture; Nanocrystalline Alloys; Rolling Texture, Metals and Alloys; Deformation Texture; Rolled Polycrystalline Nickel Cobalt Alloys; Materials Science
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Radhakrishnan, M. (2013). Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys. (Thesis). Indian Institute of Science. Retrieved from http://etd.iisc.ernet.in/handle/2005/2623 ; http://etd.ncsi.iisc.ernet.in/abstracts/3400/G26264-Abs.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Radhakrishnan, Madhavan. “Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys.” 2013. Thesis, Indian Institute of Science. Accessed January 23, 2020.
http://etd.iisc.ernet.in/handle/2005/2623 ; http://etd.ncsi.iisc.ernet.in/abstracts/3400/G26264-Abs.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Radhakrishnan, Madhavan. “Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys.” 2013. Web. 23 Jan 2020.
Vancouver:
Radhakrishnan M. Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys. [Internet] [Thesis]. Indian Institute of Science; 2013. [cited 2020 Jan 23].
Available from: http://etd.iisc.ernet.in/handle/2005/2623 ; http://etd.ncsi.iisc.ernet.in/abstracts/3400/G26264-Abs.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Radhakrishnan M. Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys. [Thesis]. Indian Institute of Science; 2013. Available from: http://etd.iisc.ernet.in/handle/2005/2623 ; http://etd.ncsi.iisc.ernet.in/abstracts/3400/G26264-Abs.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Indian Institute of Science
30.
Radhakrishnan, Madhavan.
Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys.
Degree: 2013, Indian Institute of Science
URL: http://hdl.handle.net/2005/2623
► Plastic deformation of metals and alloys are invariably accompanied by the development of texture. The origin of texture is attributed to the deformation micro-mechanisms associated…
(more)
▼ Plastic deformation of metals and
alloys are invariably accompanied by the development of texture. The origin of texture is attributed to the deformation micro-mechanisms associated with processing. The face-centered cubic (FCC) metals and
alloys are known to exhibit two distinct types of textures when subjected to large strain rolling deformation, namely, (i) Cu-type texture, commonly seen in high/medium stacking fault energy (SFE) materials, (ii) Bs-type texture in low SFE materials. The circumstances that could result in the formation of Bs-type texture in low SFE materials still remains an open question and no definite mechanism has been uniquely agreed upon.
Apart from the SFE, grain size could also influence the deformation mechanism and hence the deformation texture. It is well known that in materials with grain sizes less than 100 nm (referred to as nano-crystalline materials), the microstructures contain large fraction of grain boundaries. This subsequently introduces a variety of deformation mechanisms in the microstructure involving grain boundary-mediated processes such as grain boundary sliding and grain rotation, in addition to slip and twinning. A clear understanding of texture evolution in nano-crystalline materials, particularly at large strains, is a topic that remains largely unexplored.
The present work is an attempt to address the aforementioned issues pertaining to the evolution of deformation texture, namely, (i) the effect of SFE and (ii) the effect of grain size, in FCC metals and
alloys. Nickel-cobalt
alloys are chosen as the model system for the present investigation. The addition of cobalt to nickel leads to a systematic reduction of SFE as a function of cobalt content. In this thesis, three
alloys of Ni-Co system have been considered, namely, nickel – 20 wt.% cobalt, nickel – 40 wt.% cobalt and nickel – 60 wt.% cobalt. For a comparison, pure nickel has also been subjected to similar study.
Chapter 1 of the thesis presents a detailed survey of literature pertaining to the evolution of rolling textures in FCC metals and
alloys, and chapter 2 includes the details of the experimental techniques and characterization procedures, which are commonly employed for the entire work.
Chapter 3 addresses the effect of stacking fault energy on the evolution of rolling texture. The materials subjected to study in this chapter are microcrystalline Ni-Co
alloys. The texture evolution in Ni-20Co is very similar to pure Ni, and a characteristic Cu-type rolling texture is observed. The evolution of texture in these materials is primarily attributed to the intense dislocation activity throughout the deformation stages. In Ni-40Co, a medium SFE material, the rolling texture was predominantly Cu-type up to a strain of ε = 3 (95% thickness reduction). However, beyond this strain level, namely at ε = 4 (98%), the texture gets transformed to Bs-type with orientations maxima predominantly close to Goss ({110} <001>) position. Simultaneously, the Cu component which was dominant until 95% reduction has…
Advisors/Committee Members: Suwas, Satyam.
Subjects/Keywords: Microcrystalline Nickel-Cobalt Alloys; Nanocrystalline Nickel-Cobalt Alloys; Face Centered Cubic (FCC) Metals and Alloys; Nanocrystalline Nickel Alloys; Microcrystalline Nickel Alloys; Microcrystalline Alloys; Polycrystalline Metals; Stacking Fault Energy Alloys; Crystalline Texture; Nanocrystalline Alloys; Rolling Texture, Metals and Alloys; Deformation Texture; Rolled Polycrystalline Nickel Cobalt Alloys; Materials Science
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Radhakrishnan, M. (2013). Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys. (Thesis). Indian Institute of Science. Retrieved from http://hdl.handle.net/2005/2623
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Radhakrishnan, Madhavan. “Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys.” 2013. Thesis, Indian Institute of Science. Accessed January 23, 2020.
http://hdl.handle.net/2005/2623.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Radhakrishnan, Madhavan. “Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys.” 2013. Web. 23 Jan 2020.
Vancouver:
Radhakrishnan M. Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys. [Internet] [Thesis]. Indian Institute of Science; 2013. [cited 2020 Jan 23].
Available from: http://hdl.handle.net/2005/2623.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Radhakrishnan M. Role Of Stacking Fault Energy On Texture Evolution In Micro- And Nano-Crystalline Nickel-Cobalt Alloys. [Thesis]. Indian Institute of Science; 2013. Available from: http://hdl.handle.net/2005/2623
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
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