Article
Mechanics
Huan Li, Xiang Cheng, Wenyu Zhang
Summary: We present a nonlocal phase-field framework for modeling ductile fracture using an extended Gurson-type model. The model considers both intervoid necking and void shearing mechanisms in the crack driving force for phase-field evolution. By introducing a modified phenomenological function of nonlocal damage via a thermodynamic approach, void coalescence is considered. Numerical implementation of the model in commercial software (e.g., ABAQUS) is discussed, and several numerical benchmark examples are presented to demonstrate the predictive ability of the proposed model. Experimental verification shows that the current model alleviates the issues of pathological mesh-dependency and transferability.
Article
Materials Science, Multidisciplinary
M. E. Torki, A. A. Benzerga, J. -B. Leblond
Summary: Two recent models of void coalescence in columns are reviewed to provide simpler approximations for the effective yield surface. These approximations, unlike the exact criteria, do not preserve upper bounds but offer more flexibility in numerical implementation. Both models involve limit analysis on a cylindrical void embedded in a cylindrical cell. The accuracy of the approximations is evaluated by comparing them directly to the exact criteria for different sets of internal parameters.
MECHANICS OF MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
M. E. Torki, F. A. Medrano, A. A. Benzerga, J. -B. Leblond
Summary: Void coalescence in columns (or necklace coalescence) is a mechanism of void link-up in metal alloys and polymers, which has been confirmed through computation and physical observation but received little attention in literature. This study analyzed the phenomenon using limit analysis and homogenization theories, considering a cylindrical unit cell with a finite height cylindrical void under axially symmetric loading. The predictions were compared with other yielding modes and assessed against finite element-based limit analysis.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Materials Science, Multidisciplinary
A. Amine Benzerga
Summary: This paper discusses the plasticity of porous materials from a fundamental standpoint. It focuses on the concept of unhomogeneous yielding, which involves the yielding and plastic flow under gradient-free macroscopically nonuniform deformation. The nonuniformity is represented by strain localization in one or more bands of finite thickness. The paper presents a general theory for the finite number of bands or yield systems, with a dependence on the resolved normal stress.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Mechanics
Matthieu Marteleur, Julien Leclerc, Marie-Stephane Colla, Van-Dung Nguyen, Ludovic Noels, Thomas Pardoen
Summary: The study investigates the ductile fracture behavior of high strength steel using experimental results and models to build a predictive framework. The research reveals that the alignment of long inclusion axes leads to significant failure anisotropy, despite isotropic plastic behavior.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Mechanics
Vincent Grolleau, Christian C. Roth, Dirk Mohr
Summary: A novel experimental set-up has been proposed for in-plane torsion experiments on grooved disk specimens, featuring an enhanced clamping system for high strength materials. Experiments on three different steels demonstrated the importance of full field strain measurements during in-plane torsion, showing periodic variation of strain fields along the gage section circumference related to material anisotropy. This observation was confirmed through a finite element study covering a wide range of anisotropic Hill'48 materials with non-associated plastic flow.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Multidisciplinary Sciences
Shiteng Zhao, Sheng Yin, Xiao Liang, Fuhua Cao, Qin Yu, Ruopeng Zhang, Lanhong Dai, Carlos J. Ruestes, Robert O. Ritchie, Andrew M. Minor
Summary: The deformation and failure mechanisms of equiatomic CrCoNi medium-entropy alloy were investigated through powerful laser-driven shock experiments. Profuse planar defects, including stacking faults, nanotwins, and hexagonal nanolamella, were generated during shock compression, forming a three-dimensional network. The alloy exhibited strong tensile deformation and numerous voids were observed in the vicinity of the fracture plane during shock release. High defect populations, nanorecrystallization, and amorphization were found adjacent to these areas of localized deformation. Molecular dynamics simulations confirmed the experimental results and suggested that deformation-induced defects govern the growth of voids and delay their coalescence. These findings indicate that CrCoNi-based alloys are impact resistant, damage tolerant, and potentially suitable for applications under extreme conditions.
Article
Mechanics
Y. Xiao, K. L. Nielsen, C. F. Niordson
Summary: Void interaction leading to coalescence is the mechanism for ductile failure under intense shearing. Micro-mechanisms like void collapse, elongation, and rotation in the material have been studied using unit cell simulations, showing that gradient strengthening within the matrix delays loss of load-carrying capacity. The results also indicate that the void mechanism is sensitive to changes in applied load, hardening, and initial void volume fraction at small scales.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2021)
Article
Mechanics
Julien Leclerc, Matthieu Marteleur, Marie-Stephane Colla, Thomas Pardoen, Ludovic Noels, Van-Dung Nguyen
Summary: The study on ductile fracture behavior of high strength steel utilized a micromechanics-based approach to propose a numerical model based on the Gurson-Tvergaard-Needleman model. By identifying parameters through inverse modeling, the model was shown to adequately predict the effects of stress triaxiality and Lode parameter on fracture strain and anisotropy. The damage-to-crack transition framework successfully reproduced experimental observations of cup-cone and slant fracture paths.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Materials Science, Multidisciplinary
I. A. Khan, A. Srivastava, A. Needleman, A. A. Benzerga
Summary: This study investigates the three-dimensional finite deformation of necking and failure in rectangular tensile bars using a constitutive relation for porous material plasticity. The research shows the appearance of slant fracture in plane strain tension and the emergence of a cup-cone like failure region in square cross-section bars.
INTERNATIONAL JOURNAL OF FRACTURE
(2021)
Article
Mechanics
Y. Xiao, C. F. Niordson, K. L. Nielsen
Summary: In a shear-dominated stress state, pre-existing voids undergo rotation, elongation, and closure to form micro-cracks that interact through void coalescence, potentially leading to a loss of load-carrying capacity. Gradient strengthening affects the macroscopic strain and plastic flow localization leading to coalescence. The orientation and size of the voids, as well as the material microstructure, play significant roles in material ductility and plastic deformation prior to coalescence.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Mechanics
Xiaofan Liu, Shen Yan, Kim J. R. Rasmussen, Gregory G. Deierlein
Summary: This study investigates the influence of stress triaxiality on fracture strain and fills the gap in validating the exponential model under medium to low stress triaxiality. By comparing test specimens with similar Lode angle parameters, the effect of stress triaxiality is examined within each group. The results verify that the void growth-based exponential function accurately reflects the effect of stress triaxiality for steels over a broad range of stress triaxialities.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Sagi Chen
Summary: Ductile fracture involves the nucleation, growth, and coalescence of microvoids on the fracture surface, which can be either homogeneous or stochastically heterogeneous. The study found that heterogeneous void nucleation reduces porosity accumulation and stress triaxiality, while embedding a geometrical pore increases averaged triaxiality regardless of void nucleation heterogeneity. The ductile failure process evolves gradually from an initial homogeneous sheet with heterogeneous void nucleation towards a final void-containing sheet, with changes in stress and porosity fields.
INTERNATIONAL JOURNAL OF FRACTURE
(2022)
Article
Materials Science, Multidisciplinary
Sadek Gouasmi, Mohamed Mokhtaria, Amir Slamene, Billel Hamza, Habib Benzaama, Elamine Abdelouahed, Loubna Nadji
Summary: The evolution of preexisting voids causes damage to metal structures with large plastic deformation. In the ABAQUS-Explicit computer code, the damage by the Gurson-Tvergaard-Needleman model (GTN model) is included in the porous failure criteria law. The numerical predictions using the GTN model are very sensitive to the calibrations of these parameters of the experimental results.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Alan Xu, Michael Saleh, Dhriti Bhattacharyya
Summary: The effects of hole shape and orientation on the mechanical properties of micro-scale 2D honeycomb structures were investigated. The results showed significant changes in strength and ductility depending on the orientation and shape of the holes. Samples with 30 degrees oriented hexagonal holes had the lowest strength and highest ductility, while samples with circular holes showed the greatest yield and tensile strength. Samples with 0 degrees orientated hexagonal holes had higher strength and lower ductility compared to the 30 degrees orientated ones.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Mechanics
Z. Xue, M. G. Pontin, F. W. Zok, J. W. Hutchinson
ENGINEERING FRACTURE MECHANICS
(2010)
Article
Engineering, Mechanical
Kumar P. Dharmasena, Haydn N. G. Wadley, Zhenyu Xue, John W. Hutchinson
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2008)
Article
Engineering, Mechanical
Yihui Zhang, Zhenyu Xue, Liming Chen, Daining Fang
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2009)
Article
Mechanics
Zhenyu Xue, John W. Hutchinson
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2008)
Editorial Material
Mechanics
Ashkan Vaziri, Zhenyu Xue, Vikram S. Deshpande, Horacio D. Espinosa
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2009)
Article
Mechanics
Z. Xue, A. G. Evans, J. W. Hutchinson
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2009)
Article
Materials Science, Multidisciplinary
Yihui Zhang, Zhenyu Xue, Xinming Qiu, Daining Fang
JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES
(2008)
Article
Materials Science, Multidisciplinary
Z. Xue, A. Vaziri, J. W. Hutchinson
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2008)
Article
Nanoscience & Nanotechnology
Yanping Cao, Zhenyu Xue, Xi Chen, Dierk Raabe
SCRIPTA MATERIALIA
(2008)
Article
Materials Science, Multidisciplinary
Xi Wang, Yves Bellouard, Zhenyu Xue, Joost J. Vlassak
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2008)
Article
Materials Science, Multidisciplinary
Haydn N. G. Wadley, Kumar P. Dharmasena, Doug T. Queheillalt, Yungchia Chen, Philip Dudt, David Knight, Ken Kiddy, Zhenyu Xue, Ashkan Vaziri
JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES
(2007)
Article
Materials Science, Multidisciplinary
Ashkan Vaziri, Zhenyu Xue, John W. Hutchinson
JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES
(2007)
Article
Materials Science, Multidisciplinary
L. F. Mori, S. Lee, Z. Y. Xue, A. Vaziri, D. T. Queheillalt, K. P. Dharmasena, H. N. G. Wadley, J. W. Hutchinson, H. D. Espinosa
JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES
(2007)
Article
Materials Science, Multidisciplinary
Ashkan Vaziri, Zhenyu Xue
JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES
(2007)
Article
Mechanics
Xiaolong Liu, Kelian Luo, Pengcheng Gao, Tao Cong, Xi Wang, Wenjing Wang
Summary: This paper investigates the formation mechanisms of the zig-zag crack region on the shattered rim of railway wheels. The zig-zag crack region, identified as a typical region for crack propagation in rolling contact fatigue behavior, was observed using scanning electron microscopy and transmission electron microscopy. The formation of the zig-zag morphology is attributed to the periodic deflection of the propagation path relative to the initial propagation plane, caused by the limited plastic deformation zone at the crack tip. Grain refinement and secondary cracks in the zig-zag crack region are a result of the large compressive and shear stresses induced by rolling contact loading.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Anastasia Iziumova, Aleksei Vshivkov, Ivan Panteleev, Virginia Mubassarova, Oleg Plekhov, Denis Davydov
Summary: The aim of this study was to investigate the correlation between structural, acoustic emission, and thermal characteristics of fatigue crack growth in titanium alloys. Cluster analysis of the acoustic emission signals revealed two different types of signals observed during the fatigue crack development. It was experimentally demonstrated that the stored energy tends to reach an asymptotic value at the final stage of fatigue crack growth and this is correlated with the twinning process intensification in titanium alloy Ti Grade 2. A correlation was assumed between the stages of change in heat flux, the cumulative energy of the first cluster of acoustic emission signals, and the crack length.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
M. Vieira de Carvalho, I. A. Rodrigues Lopes, F. M. Andrade Pires
Summary: This study investigates the numerical challenges of fracture mechanics models within implicit quasi-static frameworks and proposes an instability criterion. The ratio of cohesive to internal power is identified as a crucial factor. Two strategies for handling fracture problems with instabilities are discussed and a comparative assessment is performed. The study also examines more complex material responses, including transformation-induced plasticity effects.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Thomas Duminy, Aurelien Doitrand, Sylvain Meille
Summary: This study conducted in situ wedge splitting tests on millimeter-size PMMA samples and proposed a method to determine the material tensile strength and critical energy release rate using digital image correlation and a full finite element implementation of the coupled criterion.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Xin Chang, Xingyi Wang, Chunhe Yang, Yintong Guo, Yanghui Wan
Summary: The influence of cyclic thermal shock and high-temperature acid etching on the Mode I fracture of shale was investigated in this study. It was found that cyclic thermal shock severely degrades the strength and fracture toughness of shale, while high-temperature acid etching treatment improves the fracture toughness. These findings are valuable for optimizing process parameters to reduce initiation pressure in deep shale formations.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Liaojun Yao, Mingyue Chuai, Zhangming Lyu, Xiangming Chen, Licheng Guo, R. C. Alderliesten
Summary: Methods based on fracture mechanics have been widely used in fatigue delamination growth (FDG) characterization of composite laminates. This study proposes appropriate similitude parameters to represent FDG behavior with different R-ratios.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Zesheng Zang, Zhonghui Li, Yue Niu, Shan Yin
Summary: This study conducted experiments and recorded signals to investigate the fracture behavior and damage evolution characteristics of coal samples. The results showed that as loading proceeds, the stress, electric potential (EP), and acoustic emission (AE) values increase, and EP and AE signals are excited when stress drops. The fracture behavior of coal samples is altered by flaw inclination, and the destruction mode becomes increasingly complicated. The damage evolution characteristics of coal samples can be evaluated and analyzed by defining the coefficient of variation (CV value) of EP and the b value of AE.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Clotilde Berdin, Nathalie Prud'homme
Summary: In this study, zirconia layers with different fractions of tetragonal phase and thicknesses were tested for multi-cracking behavior. Cracks perpendicular to the tensile direction were observed, showing a blunting effect into the substrate. The ratio of crack spacing at saturation to layer thickness decreased as the layer thickness increased. Unit cell modeling was used to establish a relationship between crack spacing and layer strength, which fell within the bounds of Hu and Evans model and was found to be insensitive to the tetragonal zirconia fraction.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Huadong Zhang, Weichen Kong, Y. H. Liu, Yuh J. Chao
Summary: Williams' series expansion crack tip solution in linear elasticity is modified to include a uniform crack face pressure. Practical methods to calculate T-stress from near crack tip stresses are outlined. The analytical results are consistent with numerical results.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Jiahao Kong, Haoyue Han, Tao Wang, Guangyan Huang, Zhuo Zhuang
Summary: This paper introduces a phase-field model for polymer foam materials by combining the phase-field method with the crushable foam model. The model is calibrated using experimental data and successfully simulates the fracture processes of polyurethane under different loading conditions. The study is important for the engineering applications of polymer foam materials.
ENGINEERING FRACTURE MECHANICS
(2024)