Article
Materials Science, Ceramics
Shingo Ozaki, Kazuki Yamagata, Chihiro Ito, Takuma Kohata, Toshio Osada
Summary: In this study, a finite element analysis methodology was proposed to predict the stochastic fracture behavior of ceramics based on microstructural features obtained by scanning electron microscopy and X-ray computed tomography. The analysis results confirmed that the proposed method can reasonably predict the strength scatter in ceramics.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Engineering, Mechanical
Matthias Rettl, Martin Pletz, Clara Schuecker
Summary: An efficient two-scale approach for predicting mode I crack initiation from 2D notches based on the Coupled Criterion is proposed. The method combines a local model and a crack model to analyze multiple positions on a notch and reliably identify the critical position. The predicted results of this method have smaller deviations compared to conventional methods.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Materials Science, Composites
Royson Donate Dsouza, Donato Di Vito, Jarno Jokinen, Mikko Kanerva
Summary: The accurate determination of interfacial strength in composites is a significant challenge due to the complexity of the microbond (MB) test. This study provides a thorough analysis of the MB test through finite element simulations and identifies residual stresses as an important factor affecting the results.
POLYMER COMPOSITES
(2023)
Article
Engineering, Mechanical
Lei Shi, Kai Luo, Jiangang Wang, Ding Feng, Hong Zhang, Xinjian Cao
Summary: The study found that large-scale oxide metallurgical inclusions near the casing caused the casing to crack, while the casing was subjected to stress exceeding its strength limit resulting in fracture. Recommendations include controlling heat treatment processes, optimizing material structure, rigorous testing of casing performance, and establishing a real-time analysis system.
ENGINEERING FAILURE ANALYSIS
(2021)
Article
Engineering, Mechanical
Ahmed Azeez, Daniel Leidermark, Mikael Segersall, Robert Eriksson
Summary: In warm pre-stressing (WPS), the fracture resistance of cracked steel components is increased under certain temperature-load histories. This beneficial effect of WPS improves safety margins and can potentially extend fatigue life. However, understanding and predicting the WPS effects are crucial for utilizing these benefits.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Mechanics
Jian Deng, Pu Xue, Qiao Zhi Yin, Tian Jian Liu, Xin Wei Wang
Summary: In this study, a three-dimensional damage analysis framework based on the finite element method was proposed to predict the damage evolution and load-bearing capacity of fiber-reinforced composites. The framework accounted for stress interaction, coupling effect, and addressed the issue of finite element mesh dependency.
COMPOSITE STRUCTURES
(2022)
Article
Medicine, Legal
C. Then, K. Nelson, T. J. Vogl, K. E. Roth
Summary: Nearly six decades after the assassination of President John F. Kennedy, the majority of Americans still doubt the official reports on the direction of the fatal shot. However, a recent investigation using computational simulations suggests that the official reports may be accurate, as the simulation results align with the documented evidence.
FORENSIC SCIENCE INTERNATIONAL
(2022)
Article
Engineering, Geological
Yousef Navidtehrani, Covadonga Betegon, Robert W. Zimmerman, Emilio Martinez-Paneda
Summary: This study uses the Griffith criterion and finite element analysis to evaluate the conditions and validity of the Brazilian test. It finds that the range of conditions where the Brazilian test is valid is narrower than previously assumed, and current practices and standards are inappropriate for many rock-like materials. The study also proposes a test protocol and showcases its validity through case studies and a MATLAB App.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Mechanics
Xiaona Peng, Xiang Li, Guochun Liu, Jian Zhao
Summary: A new fast approach based on finite fracture mechanics and finite element methods was developed to predict the net-tension failure strength of multi-bolt composite joints. The method efficiently calculates stress distribution and stress intensity factor, which can address different problems and validate the results through comparison with test data.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2021)
Article
Materials Science, Multidisciplinary
Yu Foong Lam, Taufiq Abdullah, Kedar Kirane
Summary: This work investigates the relationship between dynamic crack penetration and deflection at a material interface for materials with strain rate dependent damage evolution. A strain rate dependent continuum damage mechanics (CDM) model is used to analyze the behavior, where the material point softening damage law scales with the strain rate. The model is calibrated and validated with experimental data, and shows good prediction of crack behavior. It is found that the local strain rates at the interface significantly affect the bulk and interface strengths and toughnesses, resulting in increased crack penetration. Boundary conditions also play a significant role in predicting cracking behavior.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Materials Science, Composites
Alireza Taherzadeh-Fard, Alejandro Cornejo, Sergio Jimenez, Lucia Gratiela Barbu
Summary: The present study investigates the delamination behavior of laminated composites in different loading modes using a homogenization theory of mixtures. Delamination damage is introduced at the bulk level by eliminating explicit representation of interfaces. Potential delamination planes are identified based on interfacial stresses, and damage evolution is calculated independently for each mode using a stress-based formulation. An arc-length strategy is employed to solve equilibrium equations due to snap-back effects. The reliability of the adopted mixing theory is assessed by comparing results with micromechanical models in fiber metal laminate structures. Good agreement is observed in mode I, mode II, and mixed mode configurations, indicating the effectiveness of the proposed method.
COMPOSITES SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Mechanical
L. M. Martulli, A. Bernasconi
Summary: In this study, a new VCCT-based 3D fatigue propagation algorithm (SSF) is introduced to accurately simulate the fatigue propagation of delamination defects. Compared to the benchmark algorithm, the SSF significantly reduces computational time by three orders of magnitude and achieves better accuracy. This work establishes a more efficient modelling technique for fatigue delamination propagation.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Materials Science, Composites
Nazanin Pournoori, Oscar Rodera, Jarno Jokinen, Mikko Hokka, Mikko Kanerva
Summary: This study provides a detailed analysis of failure prediction for a glass fiber reinforced plastic (GFRP) composite under different strain rates. The simulations using the 3D Hashin failure criterion accurately predicted the onset of failure at various strain rates without the need for fitting parameters. The dominant failure mode in simulations was inter-fiber failure, and the criterion predicted failure onset at a low strain level close to experimental results, with a small difference and coefficient of variation.
COMPOSITES SCIENCE AND TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Gianluca Roscioli, Matej Repka, Stella Pedrazzini, Cemal Cem Tasan
Summary: It is found that the direction of crack propagation and failure mechanism in coated carbide-rich martensitic stainless steels changes with increasing corrosion severity.
Article
Engineering, Manufacturing
E. Polyzos, A. Katalagarianakis, D. Van Hemelrijck, L. Pyl
Summary: This article analyzes delamination tests of nylon 3D-printed specimens reinforced with carbon fibers by employing various analytical methods and numerical models. The results are well in agreement with experimental data, supporting the use of stochastic techniques in combination with linear fracture mechanics for the delamination analysis of 3D-printed composites.
ADDITIVE MANUFACTURING
(2021)
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)