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Rutgers University
1.
Karacor, Mehmet Basar, 1982-.
Surface directed electrokinetic flows in microfluidic devices:.
Degree: MS, Mechanical and Aerospace Engineering, 2009, Rutgers University
URL: http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.000051839 
► Electroosmotic flow control in microfluidic devices is an important and challenging problem, as electroosmosis directly influences separation efficiencies in lab-on-chip applications. In this study, a…
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▼ Electroosmotic flow control in microfluidic devices is an important and challenging problem, as electroosmosis directly influences separation efficiencies in lab-on-chip applications. In this study, a non-mechanical passive flow directing method is presented for electrokinetically driven flow. Due to the high surface-area-to-volume (SA/V) ratio, surface properties dominate the flow in microfluidic channels. For electrokinetically driven flows, the main surface property affecting electroosmotic flows is the surface ζ potential, which is related to the effective surface charge density. By changing the effective surface charge density, the electroosmotic flow rates of charged species can be controlled in microfluidic channels. In this work, to change the effective surface charge density, surfaces were chemically modified with –Br, –NH2 and –CH3 functional groups by ‘click’ chemistry. Since these functional surface layers are integrated within model glass microfluidic devices prepared by standard microfabrication procedures, the first step was to investigate the stability of the adherent surface layers to a variety of microfabrication conditions. A model “Y” shaped glass microfluidic device was developed. One leg of this model microfluidic device was selectively chemically modified to alter the ζ potential and thereby increase or decrease the electroosmotic flow with respect to rest of the device. Electroosmotic flow is visualized by using marker dyes under a fluorescent microscope. In addition, experiments were validated by using the CFD code in COMSOL. The experiments concluded that the surface layers are stable to a variety of conditions including a wide pH range (pH 3 – pH 11), solvent exposure, acid and base exposure, and UV light. Extreme conditions such as a piranha solution or oxidative plasma degrade the surface layers. Electrokinetic flow experiments show that depending on the charge of a species the electroosmotic flow is preferentially directed as a function of the ζ potential in the microfluidic channels.
Advisors/Committee Members: Karacor, Mehmet Basar, 1982- (author), Bottega, William (chair), Prakash, Shaurya (internal member), Diez-Garias, Javier (internal member), Bagchi, Prosenjit (internal member).
Subjects/Keywords: Electrokinetics; Microfluidics
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APA (6th Edition):
Karacor, Mehmet Basar, 1. (2009). Surface directed electrokinetic flows in microfluidic devices:. (Masters Thesis). Rutgers University. Retrieved from http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.000051839
Chicago Manual of Style (16th Edition):
Karacor, Mehmet Basar, 1982-. “Surface directed electrokinetic flows in microfluidic devices:.” 2009. Masters Thesis, Rutgers University. Accessed February 21, 2019.
http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.000051839.
MLA Handbook (7th Edition):
Karacor, Mehmet Basar, 1982-. “Surface directed electrokinetic flows in microfluidic devices:.” 2009. Web. 21 Feb 2019.
Vancouver:
Karacor, Mehmet Basar 1. Surface directed electrokinetic flows in microfluidic devices:. [Internet] [Masters thesis]. Rutgers University; 2009. [cited 2019 Feb 21].
Available from: http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.000051839.
Council of Science Editors:
Karacor, Mehmet Basar 1. Surface directed electrokinetic flows in microfluidic devices:. [Masters Thesis]. Rutgers University; 2009. Available from: http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.000051839
Rutgers University
2.
Berkowitz, Ron.
An integrated environment for simulation and control of mobile robots.
Degree: MS, Mechanical and Aerospace Engineering, 2011, Rutgers University
URL: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057503
► There have been increased interests in mobile robot research due to its many applications in areas such as material handling, explorations in hazardous environments, and…
(more)
▼ There have been increased interests in mobile robot research due to its many applications in areas such as material handling, explorations in hazardous environments, and military missions under extreme conditions. Many control schemes and robot systems have been developed, yet most of these systems eventually become individual experiments that are unique or specific to particular applications. It is very difficult to verify or reuse the controls developed and build upon the existing knowledge. We argue that it is necessary to develop an integrated experiment and simulation environment equipped with a user-friendly interface to examine existing controls and eventually serve as an experimental testbed for mobile robot research. The main contributions of this thesis are the design and integration of a hardware in the loop simulation environment for mobile robot control and navigation. We developed an easy to use graphical user interface (GUI) that can provide the users with the overall access to various robot functions including sensor feedback, object recognition, and tools for implementing the control strategies to study robot behaviors.
Advisors/Committee Members: Berkowitz, Ron (author), Jaluria, Yogesh (chair), Baruh, Haim (internal member), Cook-Chennault, Kimberly (internal member), Song, Peng (internal member), Bottega, William (internal member).
Subjects/Keywords: Mobile robots – Research; Mobile robots – Research – Simulation methods
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APA (6th Edition):
Berkowitz, R. (2011). An integrated environment for simulation and control of mobile robots. (Masters Thesis). Rutgers University. Retrieved from http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057503
Chicago Manual of Style (16th Edition):
Berkowitz, Ron. “An integrated environment for simulation and control of mobile robots.” 2011. Masters Thesis, Rutgers University. Accessed February 21, 2019.
http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057503.
MLA Handbook (7th Edition):
Berkowitz, Ron. “An integrated environment for simulation and control of mobile robots.” 2011. Web. 21 Feb 2019.
Vancouver:
Berkowitz R. An integrated environment for simulation and control of mobile robots. [Internet] [Masters thesis]. Rutgers University; 2011. [cited 2019 Feb 21].
Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057503.
Council of Science Editors:
Berkowitz R. An integrated environment for simulation and control of mobile robots. [Masters Thesis]. Rutgers University; 2011. Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057503
Rutgers University
3.
Titovich, Alexey, 1987-.
Nonsmooth impact mechanics of a free falling body.
Degree: MS, Mechanical and Aerospace Engineering, 2011, Rutgers University
URL: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057701
► In this study, several models are developed for analyzing the oblique impact of a container dropped from a height above the impacting surface. The governing…
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▼ In this study, several models are developed for analyzing the oblique impact of a container dropped from a height above the impacting surface. The governing equations for impact of rigid bodies in the presence of friction are developed. A clear relationship for determining sliding behavior is presented. For both frictional regimes, the dependence of the energy loss on the initial parameters is analyzed. Several vibrational impact models are presented and analyzed. These models produce a transient description of the impact force and aid in the determination of the ratio of the cushion and cargo stiffness which produce the best impact outcome. The effect of aerodynamic drag prior to impact is also analyzed. The equations governing the aerodynamics form a set of coupled nonlinear differential equations. The numerical solution of these equations illustrates that there exists a point where the object’s velocity reaches a favorable minimum, which is substantially below the terminal velocity. An approximate solution, obtained by decoupling the aerodynamic equations, is presented and validated. Both the rigid body impact mechanics and the aerodynamics are combined in a simulation code capable of analyzing subsequent impact. The simulated tumbling distances for a container, which was designed for the U.S. Army, are compared to experimental drop test data. The results validate the use of the rigid body model for this type of container.
Advisors/Committee Members: Titovich, Alexey, 1987- (author), Baruh, Haim (chair), Bottega, William J. (internal member), Elsayed, Elsayed A. (internal member).
Subjects/Keywords: Nonlinear mechanics; Force and energy; Tribology; Contact mechanics
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APA (6th Edition):
Titovich, Alexey, 1. (2011). Nonsmooth impact mechanics of a free falling body. (Masters Thesis). Rutgers University. Retrieved from http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057701
Chicago Manual of Style (16th Edition):
Titovich, Alexey, 1987-. “Nonsmooth impact mechanics of a free falling body.” 2011. Masters Thesis, Rutgers University. Accessed February 21, 2019.
http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057701.
MLA Handbook (7th Edition):
Titovich, Alexey, 1987-. “Nonsmooth impact mechanics of a free falling body.” 2011. Web. 21 Feb 2019.
Vancouver:
Titovich, Alexey 1. Nonsmooth impact mechanics of a free falling body. [Internet] [Masters thesis]. Rutgers University; 2011. [cited 2019 Feb 21].
Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057701.
Council of Science Editors:
Titovich, Alexey 1. Nonsmooth impact mechanics of a free falling body. [Masters Thesis]. Rutgers University; 2011. Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000057701
Rutgers University
4.
Nagy, Adam Julius, 1986-.
Inertial acoustic cloaks made from three acoustic fluids.
Degree: MS, Mechanical and Aerospace Engineering, 2011, Rutgers University
URL: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061367
► This thesis provides an extensive review of acoustic wave theory in one, two (polar), and three (spherical) dimensions concluding with a study of passive, non-directional…
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▼ This thesis provides an extensive review of acoustic wave theory in one, two (polar), and three (spherical) dimensions concluding with a study of passive, non-directional cloaking. The optical theorem is derived by use of energy conservation, yielding the cross sectional scattering in two and three dimensions. A new method, the Matricant Propagator, is developed for solving the scattered pressure field in wave-object interactions. Solutions found from the Matricant Propagator method are compared with known solutions using the Global Matrix method. A review of acoustic cloaking literature is given, including numerical comparison with previously proposed cloaking models. Lastly an acoustic cloak of the inertial type, made from compressible, inviscid fluids, is proposed by layering concentric shells of only three distinct fluids. The effectiveness of the device depends upon the relative densities and compressibilities of the three fluids. Optimal results are obtained if one fluid has density equal to the background fluid, while the other two densities are much greater and much less than the background. Numerical examples display a significant reduction in scattering and were compared using multiple solution methods. It is found that use of only two unique fluids is too restrictive for cloaking, however, interesting characteristics are found where energy may be diverted such that a reduction in backscatter occurs.
Advisors/Committee Members: Nagy, Adam Julius, 1986- (author), Norris, Andrew N (chair), Bottega, William J (internal member), Guo, Zhixiong (internal member).
Subjects/Keywords: Acoustical engineering
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APA (6th Edition):
Nagy, Adam Julius, 1. (2011). Inertial acoustic cloaks made from three acoustic fluids. (Masters Thesis). Rutgers University. Retrieved from http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061367
Chicago Manual of Style (16th Edition):
Nagy, Adam Julius, 1986-. “Inertial acoustic cloaks made from three acoustic fluids.” 2011. Masters Thesis, Rutgers University. Accessed February 21, 2019.
http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061367.
MLA Handbook (7th Edition):
Nagy, Adam Julius, 1986-. “Inertial acoustic cloaks made from three acoustic fluids.” 2011. Web. 21 Feb 2019.
Vancouver:
Nagy, Adam Julius 1. Inertial acoustic cloaks made from three acoustic fluids. [Internet] [Masters thesis]. Rutgers University; 2011. [cited 2019 Feb 21].
Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061367.
Council of Science Editors:
Nagy, Adam Julius 1. Inertial acoustic cloaks made from three acoustic fluids. [Masters Thesis]. Rutgers University; 2011. Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061367
5.
Boyer, Blake R., 1982-.
Identification and ranking of critical assets within an electrical grid under threat of cyber attack.
Degree: MS, Mechanical and Aerospace Engineering, 2011, Rutgers University
URL: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061142
► This paper examines the ranking of critical assets within an electrical grid under threat of cyber attack.1 Critical to this analysis is the assumption of…
(more)
▼ This paper examines the ranking of critical assets within an electrical grid under threat of cyber attack.1 Critical to this analysis is the assumption of zero hour exploits namely, the threat of an immediate attack as soon as a vulnerability is discovered. Modeling shows that over time load fluctuations as well as other system variations will change the importance of each asset in the delivery of bulk power. As opposed to classic stability studies where risk can be shown to be greatest during high load periods, the zero hour exploit-cyber-risk assumes that vulnerabilities will be attacked as soon as they are discovered. The probability of attacks is made uniform over time to include any and all possible attacks. Examining the impact of an attack and how the grid reacts immediately following an attack will identify and determine the criticality of each asset. This work endeavors to fulfill the NERC Critical Infrastructure Protection Requirements CIP-001-1 through CIP-009-2, cyber security requirements for the reliable supply of bulk power to customers throughout North America.
Advisors/Committee Members: Boyer, Blake R., 1982- (author), Bottega, William J. (chair), Muller, Michael R. (internal member), Cook-Chennault, Kimberly (internal member), Guo, Zhixiong (James) (internal member).
Subjects/Keywords: Cyberterrorism; Interconnected electric utility systems – Security measures; Electric power distribution – Security measures
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APA (6th Edition):
Boyer, Blake R., 1. (2011). Identification and ranking of critical assets within an electrical grid under threat of cyber attack. (Masters Thesis). Rutgers University. Retrieved from http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061142
Chicago Manual of Style (16th Edition):
Boyer, Blake R., 1982-. “Identification and ranking of critical assets within an electrical grid under threat of cyber attack.” 2011. Masters Thesis, Rutgers University. Accessed February 21, 2019.
http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061142.
MLA Handbook (7th Edition):
Boyer, Blake R., 1982-. “Identification and ranking of critical assets within an electrical grid under threat of cyber attack.” 2011. Web. 21 Feb 2019.
Vancouver:
Boyer, Blake R. 1. Identification and ranking of critical assets within an electrical grid under threat of cyber attack. [Internet] [Masters thesis]. Rutgers University; 2011. [cited 2019 Feb 21].
Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061142.
Council of Science Editors:
Boyer, Blake R. 1. Identification and ranking of critical assets within an electrical grid under threat of cyber attack. [Masters Thesis]. Rutgers University; 2011. Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061142
6.
Carabetta, Pamela Marie, 1982-.
On the interaction of thermal buckling and debonding of patched structures.
Degree: PhD, Mechanical and Aerospace Engineering, 2011, Rutgers University
URL: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061144
► The widespread use of patched assemblies in engineering structures creates the need for better fundamental understanding of the failure phenomena of such structures to ensure…
(more)
▼ The widespread use of patched assemblies in engineering structures creates the need for better fundamental understanding of the failure phenomena of such structures to ensure their safe and effective usage. A structure possessing two substructures, the
“patch” and “baseplate”, with mismatched coefficients of thermal expansion is studied under thermal loading for two extreme edge conditions. The composite structure is taken as initially flawed, such that partial separation exists at the edges of the patch between the
two substructures. Two relevant failure mechanisms are sling-shot buckling and edge debonding (separation). Sling-shot buckling, first observed for perfectly intact structures under thermal loads, occurs when the structure dynamically slings from one equilibrium configuration to another in an opposite sense of deflection at a critical load. It is desired
to be able to predict and characterize buckling of the structure, and its coupling with debonding. The geometrically nonlinear problem is formulated via a variational formulation, which allows the boundaries of the domains of the structure to vary in addition to the displacements. The vanishing of the first variation of the potential energy yields governing equilibrium equations, boundary/matching conditions, and transversality
conditions. The transversality condition yields a Griffith type delamination criterion. A closed-form solution is obtained after recasting the problem in a mixed formulation. A stability analysis is performed using the second variation of the potential energy functional. The partially debonded structure is seen to possess a “dual nature”, where it is structurally different depending on the deflection, due to the existence of the initial
flaw. It experiences sling-shot buckling, which, coupled with the structure’s duality leads to what we refer to as “Buckle Trapping.” It is suggested that, for certain critical
temperature fields, the structure oscillates dynamically between unstable equilibrium configurations. In addition, examination of the energy release rate against the bond size reveals a variety of possible behaviors, dependent on flaw size, temperature difference,
and bond strength. It is observed how and when separation leads to thermal buckling, and vice versa. Through this analysis, the onset, extent, and stability of debonding, as well as the relationship with buckling, are diagnosed and characterized.
Advisors/Committee Members: Carabetta, Pamela Marie, 1982- (author), Bottega, William J (chair), Baruh, Haim (internal member), Benaroya, Haym (internal member), Yong, Yook-Kong (outside member).
Subjects/Keywords: Thermal stresses; Structural engineering
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APA (6th Edition):
Carabetta, Pamela Marie, 1. (2011). On the interaction of thermal buckling and debonding of patched structures. (Doctoral Dissertation). Rutgers University. Retrieved from http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061144
Chicago Manual of Style (16th Edition):
Carabetta, Pamela Marie, 1982-. “On the interaction of thermal buckling and debonding of patched structures.” 2011. Doctoral Dissertation, Rutgers University. Accessed February 21, 2019.
http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061144.
MLA Handbook (7th Edition):
Carabetta, Pamela Marie, 1982-. “On the interaction of thermal buckling and debonding of patched structures.” 2011. Web. 21 Feb 2019.
Vancouver:
Carabetta, Pamela Marie 1. On the interaction of thermal buckling and debonding of patched structures. [Internet] [Doctoral dissertation]. Rutgers University; 2011. [cited 2019 Feb 21].
Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061144.
Council of Science Editors:
Carabetta, Pamela Marie 1. On the interaction of thermal buckling and debonding of patched structures. [Doctoral Dissertation]. Rutgers University; 2011. Available from: http://hdl.rutgers.edu/1782.1/rucore10001600001.ETD.000061144
Rutgers University
7.
Carabetta, Pamela.
Effects of geometric nonlinearities and uniform temperature fields on the detachment of patched beam-plates under pressure loading.
Degree: MS, Mechanical and Aerospace Engineering, 2007, Rutgers University
URL: http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.15793
► Patched structures have many engineering applications, ranging from aircraft repair to electronic devices and beyond. Delamination growth at the edge of the interface between the…
(more)
▼ Patched structures have many engineering applications, ranging from aircraft repair to electronic devices and beyond. Delamination growth at the edge of the interface between the substructures may lead to catastrophic results. In the spirit of preventing this, edge delamination failure is studied such that behavior may be predicted as well as characterized for a patched beam-plate structure under different physical conditions. The loading scenario on such structures includes transverse pressure and an applied uniform temperature field. These conditions are intended to mimic possible conditions under which a patched beam-plate may be used. The patched beam-plate consists of two plates: the "patch," which is of shorter length, adhered to the longer "baseplate". This composite structure is examined under various support conditions on the endpoints: hinged-free, clamped-free, hinged-fixed, and clamped-fixed.
The problem is formulated analytically, from first principles, using linear and geometrically nonlinear models. Governing equations are derived using a local force balance on an element of the structure incorporating an appropriate geometrically nonlinear thin structure theory, and can be reduced accordingly to simplify to a corresponding linear model. A Griffith type criterion, is adopted to determine the onset of delamination growth. Exact analytical solutions are obtained for nonlinear as well as linear problems and numerical simulations based on these solutions are performed using MATLAB.
Results are presented in the form of delamination growth paths, which may be interpreted physically to describe the onset, extent, and stability of the delamination growth resulting from each scenario. The effect of various physical parameters on delamination behavior is explored. The results show that a temperature difference has a profound effect on the delamination behavior of the patched plates when subject to transverse pressure, as it significantly alters the delamination growth thresholds. There are scenarios where delamination propagation begins in the absence of transverse pressure, due solely to the applied temperature difference. Conclusions are drawn and physical explanations are given for the behavior of each patched plate system. The nonlinear model reveals different delamination growth thresholds and stabilities than the linear model. It observed that the linear model does not adequately describe the salient behavior in comparison to the nonlinear model.
Advisors/Committee Members: Carabetta, Pamela (author), Bottega, William (chair), Baruh, Haim (internal member), Benaroya, Haym (internal member).
Subjects/Keywords: Composite materials – Delamination; Plates (Engineering)
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APA (6th Edition):
Carabetta, P. (2007). Effects of geometric nonlinearities and uniform temperature fields on the detachment of patched beam-plates under pressure loading. (Masters Thesis). Rutgers University. Retrieved from http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.15793
Chicago Manual of Style (16th Edition):
Carabetta, Pamela. “Effects of geometric nonlinearities and uniform temperature fields on the detachment of patched beam-plates under pressure loading.” 2007. Masters Thesis, Rutgers University. Accessed February 21, 2019.
http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.15793.
MLA Handbook (7th Edition):
Carabetta, Pamela. “Effects of geometric nonlinearities and uniform temperature fields on the detachment of patched beam-plates under pressure loading.” 2007. Web. 21 Feb 2019.
Vancouver:
Carabetta P. Effects of geometric nonlinearities and uniform temperature fields on the detachment of patched beam-plates under pressure loading. [Internet] [Masters thesis]. Rutgers University; 2007. [cited 2019 Feb 21].
Available from: http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.15793.
Council of Science Editors:
Carabetta P. Effects of geometric nonlinearities and uniform temperature fields on the detachment of patched beam-plates under pressure loading. [Masters Thesis]. Rutgers University; 2007. Available from: http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.15793
Rutgers University
8.
Barai, Pallab.
Creep resistance and strain-rate sensitivity of nanocrystalline materials.
Degree: MS, Mechanical and Aerospace Engineering, 2008, Rutgers University
URL: http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.17274
► A micromechanics-based continuum model is developed to determine the creep resistance and strain-rate sensitivity of the nanocrystalline materials. The solid is idealized as a two…
(more)
▼ A micromechanics-based continuum model is developed to determine the creep resistance and strain-rate sensitivity of the nanocrystalline materials. The solid is idealized as a two (or three) phase composite, where the grains were treated as spherical inclusions, the grain boundary as the matrix and the pores/voids as the third phase (if present in the solid) of the composite. The strain of an individual phase is taken to be the sum of elastic and creep/viscoplastic components. Within the elastic context the homogenization scheme is developed based on the Eshelby-Mori-Tanaka approach. The Laplace transform was used to convert the linear elastic homogenization
method to a linear viscoelastic one, and then to convert the viscoelastic response to viscoplastic one, during which the Maxwell viscosity of the viscoelastic phases is replaced by the secant viscosity of the viscoplastic phases. A nonlinear-rate dependent constitutive equation is assumed for both the grain interior and grain boundary to calculate the secant viscosity of the individual phase at a given stage of deformation. The drag stress of the grain interior is assumed to follow the Hall-Petch effect, but that of the grain boundary phase is taken to be size-independent. By using the field-fluctuation method, the effective stress (or effective strain rate) of the constitutive phase is derived in terms of the applied stress (or applied strain rate). The change in porosity under different loading conditions is also incorporated within the model.
The validity of the model was verified by comparing the predicted stress-strain results with the experimental data of Sanders et al. [42], Wang et al. [43] and Wang et al. [44] for the creep response, and Khan et al. [48] and Khan and Zhang [49] for the constant strain-rate loading. The model is capable of capturing both hardening and softening of material as grain size decreases from coarse grain to the nanometer range. The latter characteristic is also known as the inverse Hall-Petch effect and this occurs in both creep and constant strain-rate response. As a result, the critical grain size at which the solid has maximum strength can be estimated using this method. With the presence of porosity, the developed model is also able to capture the nonlinearity in the stress-strain plot under hydrostatic loading.
Advisors/Committee Members: Barai, Pallab (author), Weng, George (chair), Baruh, Haim (internal member), Bottega, William (internal member).
Subjects/Keywords: Materials – Creep; Nanocrystals; Nanostructured materials
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APA (6th Edition):
Barai, P. (2008). Creep resistance and strain-rate sensitivity of nanocrystalline materials. (Masters Thesis). Rutgers University. Retrieved from http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.17274
Chicago Manual of Style (16th Edition):
Barai, Pallab. “Creep resistance and strain-rate sensitivity of nanocrystalline materials.” 2008. Masters Thesis, Rutgers University. Accessed February 21, 2019.
http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.17274.
MLA Handbook (7th Edition):
Barai, Pallab. “Creep resistance and strain-rate sensitivity of nanocrystalline materials.” 2008. Web. 21 Feb 2019.
Vancouver:
Barai P. Creep resistance and strain-rate sensitivity of nanocrystalline materials. [Internet] [Masters thesis]. Rutgers University; 2008. [cited 2019 Feb 21].
Available from: http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.17274.
Council of Science Editors:
Barai P. Creep resistance and strain-rate sensitivity of nanocrystalline materials. [Masters Thesis]. Rutgers University; 2008. Available from: http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.17274
. 
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