Article
Materials Science, Multidisciplinary
J. D. Clayton
Summary: A geometrically nonlinear phase field theory is constructed to account for dissipation, rate effects, nonlinear thermoelasticity, fracture, and other structural changes in the context of continuum thermodynamics. Specialized to deformation physics pertinent to crystalline ceramics and minerals deformed at high rates and pressures, the theory provides insights into high-rate deformation mechanisms in these materials.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2021)
Article
Materials Science, Multidisciplinary
J. D. Clayton, J. A. Zorn, R. B. Leavy, M. C. Guziewski, J. Knap
Summary: Phase field simulations are used to study the effects of microstructure features on the overall strength and ductility of polycrystalline ceramic composites. The results suggest that peak strength can be increased by increasing bulk diamond content, reducing porosity, reducing graphite content, and distributing unavoidable defects uniformly. More complex interrelations among microstructures, model features, and material responses are also revealed.
INTERNATIONAL JOURNAL OF FRACTURE
(2022)
Article
Materials Science, Multidisciplinary
Yu-Sheng Lo, Thomas J. R. Hughes, Chad M. Landis
Summary: The phase-field modeling framework for linear elastic fracture mechanics problems is modified to analyze crack growth in large structures. The approach replaces sharp crack surfaces with a diffuse fracture zone, which is characterized by a length scale. However, extending the model to large structures presents challenges due to meshing requirements for the crack length scale. A new formulation is introduced to decouple the phase-field length scale from the physical process zone length scale.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Crystallography
Qianyu Shi, Hongjun Yu, Xiangyuhan Wang, Kai Huang, Jian Han
Summary: In this study, the fracture phase field model is coupled with a viscoplastic constitutive in a finite element framework, using elastic energy and inelastic energy as crack driving forces. The effects of strain rate, creep, stress relaxation, and cyclic loading on the inelastic energy contributions are tested using single-element models. The results indicate that the inelastic energy significantly accelerates the phase field evolution of viscoplastic materials, with a more pronounced effect for low-frequency cyclic loadings.
Article
Engineering, Multidisciplinary
Keita Yoshioka, Mostafa Mollaali, Olaf Kolditz
Summary: This paper proposes a diffused approach to approximate failure at interfaces with negligible space, deriving an effective interface fracture toughness and verifying its effectiveness in various scenarios.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Engineering, Multidisciplinary
Sindhu Nagaraja, Ulrich Roemer, Hermann G. Matthies, Laura De Lorenzis
Summary: This study investigates variational phase-field formulations to model zigzag crack patterns in cubic materials. The main objectives are to analyze the behavioral aspects predicted by two fourth-order models and guide the calibration of their unknown parameters, as well as to transition from a deterministic to a stochastic model by introducing a material-related random field. Statistical moments of the phase-field variable are estimated using Monte Carlo, randomized quasi-Monte Carlo, and stochastic spectral methods. The stochastic approach holds significant promise in enabling meaningful predictions of anisotropic fracture with phase-field models.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Chemistry, Physical
Scott Monismith, Jianmin Qu, Remi Dingreville
Summary: In this paper, phase-field simulations are used to investigate fracture and short circuit issues in the Li7La3Zr2O12 (LLZO) solid electrolyte. The study reveals that in the presence of a single crack, the crack propagation threshold exhibits inverse square root scaling with respect to crack length, while the short-circuit potential scales linearly with crack length. For multiple cracks, failure follows the Weibull model, and higher crack density favors failure at lower overpotentials. Additionally, the use of flawless interfacial buffers mitigates failure and allows for larger sustained currents without reaching unstable overpotentials.
JOURNAL OF POWER SOURCES
(2023)
Review
Mechanics
X. Zhuang, S. Zhou, G. D. Huynh, P. Areias, T. Rabczuk
Summary: This paper presents an overview of the theories and computer implementation aspects of phase field models (PFM) of fracture. The paper describes the advantages of PFM over other fracture methods and highlights its capabilities in practical applications.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Mingyu Gong, J. Graham, Vincent Taupin, Laurent Capolungo
Summary: The study investigates the effects of structure, stress, and temperature on the mobility of facets bounding twin domains in Mg, focusing on the growth kinetics of {10 (1) over bar2} twins. Molecular dynamics simulations are used to study the relationship between interface structures, stress, temperature, and mobility. The research also emphasizes the significance of stress relaxation mediated by misfit dislocations on the mobility of basal-prismatic interfaces.
Article
Engineering, Multidisciplinary
Jian-Ying Wu, Jing-Ru Yao, Jia-Liang Le
Summary: In this paper, a computational framework is presented to capture probabilistic fracture in heterogeneous quasi-brittle solids by combining random field theory and the phase-field cohesive zone model. The spatial variation of material properties is represented by a cross-correlated bivariate random field generated by the Karhunen-Loeve expansion. The proposed model is applied to Monte Carlo simulations of fracture in concrete structures, and the results show that the stochastic simulation results are insensitive to the phase-field length scale parameter and finite element mesh discretization, making it a viable tool for stochastic simulations of damage and fracture in quasi-brittle structures.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Chemistry, Physical
Binting Huang, Jishi Yang, Zhiheng Luo, Yang Wang, Nan Wang
Summary: The rapid solidification process often leads to high-density microstructure defects and residual thermal stress in metals. Twin boundaries, which are potentially beneficial, have been observed in rapidly solidified nanocrystalline microstructures. This study proposes a pathway for forming twin boundaries and provides a detailed derivation of strain inhomogeneities and the deformation twinning phase field method. By calculating the cooling-induced thermal strain inhomogeneity and growth thresholds for deformation twinning, it is shown that residual thermal strain hotspots in the microstructure can reach the threshold for deformation twinning when there is a significant difference in shear elastic property between grain boundaries and the bulk material.
Article
Chemistry, Physical
Reliance Jain, M. R. Rahul, Poulami Chakraborty, Rama Krushna Sabat, Sumanta Samal, Gandham Phanikumar, Raghvendra Tewari
Summary: In the present study, a novel single-phase FCC high entropy alloy was developed using the ICME approach. The composition guided by simulation was validated and the deformation behavior of the alloy at elevated temperature was discussed. This study demonstrates the rationalization of deformation behavior based on microstructure evolution using EBSD.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Multidisciplinary
Tong-Rui Liu, Fadi Aldakheel, M. H. Aliabadi
Summary: In this paper, a new and efficient virtual element scheme for phase field modeling of dynamic fracture is proposed using an explicit time integration scheme. The whole problem is divided into two parts: mechanical and damage sub-problems, treated as elastodynamic and Poisson equations respectively. Benchmark problems are validated to test the performance of the proposed numerical framework, showing good agreement with corresponding numerical and experimental studies. Moreover, VEM outperforms FEM in terms of memory efficiency and choice of element type.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Gang Zhang, Tian Fu I. Guo, Khalil Elkhodary, Shan Tang, Xu Guo
Summary: This paper presents a mixed Graph-FEM approach for the phase field modeling of fracture in plates and shells composed of nonlinearly elastic solids. The method discretizes the phase field evolution equation using a graph Laplacian on a curved surface and proposes an alternating solution strategy. It demonstrates fast convergence and robustness in modeling the fracture of plates and shells of arbitrary curvature.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Engineering, Geological
Jie Yang, Hamdi A. Tchelepi, Anthony R. Kovscek
Summary: This study presents a thermodynamically consistent rate-dependent fracture model, coupled with single-phase fluid flow, to investigate solid-fluid coupling, fluid-driven fracture propagation, and rate-dependent viscoelastic deformation. The model is based on rigorous thermodynamic principles and ensures energy conservation during fracture propagation, making it a strong basis for studying rate-dependent fracturing experiments and predicting material behaviors under new conditions.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2021)
Article
Mechanics
J. D. Clayton
MECHANICS RESEARCH COMMUNICATIONS
(2020)
Article
Mechanics
J. D. Clayton, A. D. Freed
Article
Materials Science, Multidisciplinary
J. D. Clayton, J. A. Zorn, R. B. Leavy, M. C. Guziewski, J. Knap
Summary: Phase field simulations are used to study the effects of microstructure features on the overall strength and ductility of polycrystalline ceramic composites. The results suggest that peak strength can be increased by increasing bulk diamond content, reducing porosity, reducing graphite content, and distributing unavoidable defects uniformly. More complex interrelations among microstructures, model features, and material responses are also revealed.
INTERNATIONAL JOURNAL OF FRACTURE
(2022)
Article
Chemistry, Physical
J. D. Clayton, M. Guziewski, J. P. Ligda, R. B. Leavy, J. Knap
Summary: Diamond-silicon carbide polycrystalline composite blends are studied using a computational approach that combines molecular dynamics simulations and phase field mechanics. The study shows that grain boundary geometries and local heterogeneities affect material response, and the composition of GB layers also influences the properties.
Article
Materials Science, Multidisciplinary
J. D. Clayton
Summary: A geometrically nonlinear phase field theory is constructed to account for dissipation, rate effects, nonlinear thermoelasticity, fracture, and other structural changes in the context of continuum thermodynamics. Specialized to deformation physics pertinent to crystalline ceramics and minerals deformed at high rates and pressures, the theory provides insights into high-rate deformation mechanisms in these materials.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2021)
Article
Materials Science, Multidisciplinary
John D. Clayton
Summary: Finsler differential geometry has been widely used in describing materials mechanics with microstructure, incorporating specific concepts in solid mechanics and continuous field theories. By comparing physical models in generalized Finsler spaces with standard approaches, novel, physical, and practical model predictions and equations for macroscopic and microscopic equilibrium states can be obtained.
MATHEMATICS AND MECHANICS OF SOLIDS
(2022)
Article
Materials Science, Multidisciplinary
J. D. Clayton, R. B. Leavy, J. Knap
Summary: This study presents a phase field theory that takes into account thermoelasticity, fracture, twinning, and limited slip in crystalline solids. The theory incorporates residual stresses by referencing thermoelastic strain to a reference state that may not be stress-free. It includes rate dependence, dissipated energy, and residual strain energy, and is validated for homogeneous stress states. The model is implemented in finite element calculations of polycrystalline aggregates and reveals the effects of thermal-residual stresses and other microstructure properties on deformation and failure mechanisms.
PHILOSOPHICAL MAGAZINE
(2022)
Article
Thermodynamics
J. D. Clayton, J. T. Lloyd
Summary: A continuum mechanical theory is proposed to study the deformation behavior of ferrous alloys under high-pressure, high-rate loading and large magnetic fields. The theory encompasses various physical phenomena and is consistent with the governing equations of nonlinear electromagnetic continua. Calculations demonstrate the effectiveness of the theory for ferrous polycrystals under different loading conditions.
CONTINUUM MECHANICS AND THERMODYNAMICS
(2022)
Article
Multidisciplinary Sciences
J. D. Clayton, C. L. Williams
Summary: In planar shock compression experiments, polycrystalline titanium diboride (TiB2) exhibits double-yield phenomena, different from other non-transforming ceramics. A finite-strain phase-field theory is used to simulate the shock response of TiB2, accurately depicting the longitudinal and shear stress variations. The results support a sequence of physical mechanisms involving fracture, dilatation, plastic deformation, and fragmentation. In the three-wave regime, the number and characteristics of plastic waves depend on the impact stress. The model also explains the kinks in the plastic waveforms observed in experimental data.
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2022)
Review
Materials Science, Multidisciplinary
John D. D. Clayton, Daniel T. T. Casem, Jeffrey T. T. Lloyd, Emily H. H. Retzlaff
Summary: This paper focuses on static and dynamic indentation, especially for the extraction of material properties of isotropic strain-hardening polycrystalline metals. Static indentation is considered as a specialization of dynamic indentation without inertia, rate dependence, and adiabatic heating. By using dimensional analysis, a general framework for extracting material property information from dynamic spherical indentation experiments is proposed. Experimental data from instrumented spherical indentation in a miniature Kolsky bar apparatus are evaluated through dimensional analysis. New experiments and simulations are proposed to identify the influences of material properties.
Article
Materials Science, Multidisciplinary
J. D. Clayton, J. Knap, R. B. Leavy
Summary: This article implements a phase field theory of fracture incorporating rate dependence and anisotropic elasticity to study the strength and failure modes in polycrystalline materials. It presents a new analytical solution for one-dimensional homogeneous loading at constant strain rate with crack viscosity. The three-dimensional theory is verified using finite element simulations for homogeneous microstructures and further extended to study the effects of various material properties on tensile strength, including loading rate, elastic anisotropy, and energy anisotropy.
MECHANICS OF MATERIALS
(2023)
Article
Mechanics
J. D. Clayton, R. B. Leavy, J. Knap
Summary: A phase field theory is used to study fracture mechanics, considering the influence of stress state on material strength. It is found that brittle solids are more resistant to fracture when mean stress is compressive. The theory incorporates a dissipative kinetic law that introduces rate dependence and viscous resistance to propagation. Analytical solutions are derived for one-dimensional problems of isotropic materials under various loading conditions, and three-dimensional simulations are conducted for polycrystalline microstructures. Results reveal the effects of microstructure and anisotropy on different stress states, with increasing confinement reducing the influence of these factors on average stress and ductility.
MECHANICS RESEARCH COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Aleksander Zubelewicz, John D. Clayton
Summary: Since the 1980s, constitutive modeling has shifted from phenomenological descriptions to micromechanics considerations. However, crystal plasticity remains a research challenge, particularly for the low-temperature behavior of bcc metals like molybdenum. Screw dislocations play a crucial role in the plastic flow strength, causing non-planar core structures and violating the Schmid law.
Article
Engineering, Mechanical
J. D. Clayton, J. T. Lloyd, D. T. Casem
Summary: The FE modeling shows accurate reproduction of experimental load-depth curves in dynamic indentation experiments. The dimensional analysis framework improves upon previous work and reveals the sensitivity of predicted response to variations in material properties. Extraction of quasi-static and thermal material properties can be achieved through static indentation and elevated temperature indentation experiments, respectively. The parameterized stress-strain response for Al 6061-T6 obtained from novel instrumented dynamic spherical indentation experiments and FE simulations shows good validation for strain rates up to the order of 103/s.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Materials Science, Multidisciplinary
J. D. Clayton, J. T. Lloyd
Summary: Steel may exhibit various inelastic deformation mechanisms, such as dislocation glide and deformation twinning, depending on composition, processing, and loading mode. The formation of voids and subsequent macro-cracking is also a key concern. A finite-deformation constitutive model is constructed to address these mechanisms under static and dynamic loading.
JOURNAL OF DYNAMIC BEHAVIOR OF MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Y. Liu, K. Zweiacker, C. Liu, J. T. McKeown, J. M. K. Wiezorek
Summary: The evolution of rapid solidification microstructure and solidification interface velocity of hypereutectic Al-20at.%Cu alloy after laser melting has been studied experimentally. It was found that the formation of microstructure was dominated by eutectic, alpha-cell, and banded morphology grains, and the growth modes changed with increasing interface velocity.
Article
Materials Science, Multidisciplinary
Bharat Gwalani, Julian Escobar, Miao Song, Jonova Thomas, Joshua Silverstein, Andrew Chihpin Chuang, Dileep Singh, Michael P. Brady, Yukinori Yamamoto, Thomas R. Watkins, Arun Devaraj
Summary: Castable alumina forming austenitic alloys exhibit superior creep life and oxidation resistance at high temperatures. This study reveals the mechanism behind the enhanced creep performance of these alloys by suppressing primary carbide formation and offers a promising alloy design strategy for high-temperature applications.
Article
Materials Science, Multidisciplinary
Jian Song, Qi Zhang, Songsong Yao, Kunming Yang, Houyu Ma, Jiamiao Ni, Boan Zhong, Yue Liu, Jian Wang, Tongxiang Fan
Summary: Recent studies have shown that achieving an atomically flat surface for metals can greatly improve their oxidation resistance and enhance their electronic-optical applications. Researchers have explored the use of graphene as a covering layer to achieve atomically flat surfaces. They found that high-temperature deposited graphene on copper surfaces formed mono-atomic steps, while annealed copper and transferred graphene on copper interfaces formed multi-atomic steps.
Article
Materials Science, Multidisciplinary
Jennifer A. Glerum, Jon-Erik Mogonye, David C. Dunand
Summary: Elemental powders of Al, Ti, Sc, and Zr are blended and processed via laser powder-bed fusion to create binary and ternary alloys. The microstructural analysis and mechanical testing show that the addition of Ti results in the formation of primary precipitates, while the addition of Sc and Zr leads to the formation of fine grain bands. The Al-0.25Ti-0.25Zr alloy exhibits comparable strain rates to Al-0.5Zr at low stresses, but significantly higher strain rates at higher stresses during compressive creep testing. Finite element modeling suggests that the connectivity of coarse and fine grain regions is a critical factor affecting the creep resistance of the alloys.
Article
Materials Science, Multidisciplinary
P. Jannotti, B. C. Hornbuckle, J. T. Lloyd, N. Lorenzo, M. Aniska, T. L. Luckenbaugh, A. J. Roberts, A. Giri, K. A. Darling
Summary: This work characterizes the thermo-mechanical behavior of bulk nanocrystalline Cu-Ta alloys under extreme conditions. The experiments reveal that the alloys exhibit unique mechanical properties, behaving differently from conventional nanocrystalline Cu. They do not undergo grain coarsening during extrusion and exhibit behavior similar to coarse-grained Cu.
Article
Materials Science, Multidisciplinary
Yiqing Wei, Jingwei Li, Daliang Zhang, Bin Zhang, Zizhen Zhou, Guang Han, Guoyu Wang, Carmelo Prestipino, Pierric Lemoine, Emmanuel Guilmeau, Xu Lu, Xiaoyuan Zhou
Summary: This study proposes a new strategy to modify microstructure by phase regulation, which can simultaneously enhance carrier mobility and reduce lattice thermal conductivity. The addition of Cu in layered SnSe2 induces a phase transition that leads to increased grain size and reduced stacking fault density, resulting in improved carrier mobility and lower lattice thermal conductivity.
Article
Materials Science, Multidisciplinary
Jia Chen, Zhengyu Zhang, Eitan Hershkovitz, Jonathan Poplawsky, Raja Shekar Bhupal Dandu, Chang-Yu Hung, Wenbo Wang, Yi Yao, Lin Li, Hongliang Xin, Honggyu Kim, Wenjun Cai
Summary: In this study, the structural origin of the pH-dependent repassivation mechanisms in multi-principal element alloys (MPEA) was investigated using surface characterization and computational simulations. It was found that selective oxidation in acidic to neutral solutions leads to enhanced nickel enrichment on the surface, resulting in reduced repassivation capability and corrosion resistance.
Article
Materials Science, Multidisciplinary
X. Y. Xu, C. P. Huang, H. Y. Wang, Y. Z. Li, M. X. Huang
Summary: The limited slip systems of magnesium (Mg) and its alloys hinder their wide applications. By conducting tensile straining experiments, researchers discovered a rate-dependent transition in the dislocation mechanisms of Mg alloys. At high strain rates, glissile dislocations dominate, while easy-glide dislocations dominate at low strain rates. Abundant glissile dislocations do not necessarily improve ductility.
Article
Materials Science, Multidisciplinary
M. S. Szczerba, M. J. Szczerba
Summary: Inverse temperature dependences of the detwinning stress were observed in face-centered cubic deformation twins in Cu-8at.%Al alloy. The detwinning stress increased with temperature when the pi detwinning mode was involved, but decreased when the pi/3 mode was involved. The dual effect of temperature on the detwinning stress was due to the reduction of internal stresses pre-existing within the deformation twins. The complete reduction of internal stresses at about 530 degrees C led to the equivalence of the critical stresses of different detwinning modes and a decrease in the yield stress anisotropy of the twin/matrix structure.
Article
Materials Science, Multidisciplinary
Taowen Dong, Tingting Qin, Wei Zhang, Yaowen Zhang, Zhuoran Feng, Yuxiang Gao, Zhongyu Pan, Zixiang Xia, Yan Wang, Chunming Yang, Peng Wang, Weitao Zheng
Summary: The interaction between the electrode and the electric double layer (EDL) significantly influences the energy storage mechanism. By studying the popular alpha-Fe2O3 electrode and the EDL interaction, we find that the energy storage mechanism of the electrode can be controlled by modulating the EDL.
Article
Materials Science, Multidisciplinary
Matthew R. Barnett, Jun Wang, Sitarama R. Kada, Alban de Vaucorbeil, Andrew Stevenson, Marc Fivel, Peter A. Lynch
Summary: The elastic-plastic transition in magnesium alloy Mg-4.5Zn exhibits bursts of deformation, which are characterized by sudden changes in grain orientation. These bursts occur in a coordinated manner among nearby grains, with the highest burst rate observed at the onset of full plasticity. The most significant burst events are associated with twinning, supported by the observation of twinned structures using electron microscopy. The bursts are often preceded and followed by a stasis in peak movement, indicating a certain "birth size" for twins upon formation and subsequent growth at a later stage.
Article
Materials Science, Multidisciplinary
Vaidehi Menon, Sambit Das, Vikram Gavini, Liang Qi
Summary: Understanding solute segregation thermodynamics is crucial for investigating grain boundary properties. The spectral approach and thermodynamic integration methods can be used to predict solute segregation behavior at grain boundaries and compare with experimental observations, thus aiding in alloy design and performance control.
Article
Materials Science, Multidisciplinary
Feiyu Qin, Lei Hu, Yingcai Zhu, Yuki Sakai, Shogo Kawaguchi, Akihiko Machida, Tetsu Watanuki, Yue-Wen Fang, Jun Sun, Xiangdong Ding, Masaki Azuma
Summary: This study reports on the negative and zero thermal expansion properties of Cd2Re2O7 and Cd1.95Ni0.05Re2O7 materials, along with their ultra-low thermal conductivity. Through investigations of their structures and phonon calculations, the synergistic effect of local structure distortion and soft phonons is revealed as the key to achieving these distinctive properties.
Article
Materials Science, Multidisciplinary
Thomas Beerli, Christian C. Roth, Dirk Mohr
Summary: A novel testing system for miniature specimens is designed to characterize the plastic response of materials for which conventional full-size specimens cannot be extracted. The system has an automated operation process, which reduces the damage to specimens caused by manual handling and improves the stability of the test results. The experiments show that the miniature specimens extracted from stainless steel and aluminum have high reproducibility, and the results are consistent with those of conventional-sized specimens. A correction procedure is provided to consider the influence of surface roughness and heat-affected zone caused by wire EDM.
Article
Materials Science, Multidisciplinary
Rani Mary Joy, Paulius Pobedinskas, Nina Baule, Shengyuan Bai, Daen Jannis, Nicolas Gauquelin, Marie-Amandine Pinault-Thaury, Francois Jomard, Kamatchi Jothiramalingam Sankaran, Rozita Rouzbahani, Fernando Lloret, Derese Desta, Jan D'Haen, Johan Verbeeck, Michael Frank Becker, Ken Haenen
Summary: This study investigates the influence of film microstructure and composition on the Young's modulus and residual stress in nanocrystalline diamond thin films. The results provide insights into the mechanical properties and intrinsic stress sources of these films, and demonstrate the potential for producing high-quality nanocrystalline diamond films under certain conditions.
