Article
Engineering, Mechanical
Xue-Peng Zhou, De-Guang Shang, Dao-Hang Li, Jin-Jie Wang, Yi-Ru Zhao, Wei Li
Summary: This paper presents a total life prediction method for short crack propagation under multiaxial fatigue loading considering additional damage from nonproportional loading. A new calculation method of equivalent stress range is proposed to account for the effect of shear stress on crack propagation under tensile or compressive stress, and it is further modified to consider the additional damage. The proposed method, combined with Paris formula and crack closure correction, is validated through life results for two materials, showing errors within a factor of 3.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Robert Keqi Luo
Summary: This study utilized an effective stress tensor in multi-axial stress states, fully implementing it to a non proportional case for the first time. The presented two cases demonstrated that the effective stress reached its maximum at critical locations where fatigue cracks were observed.
ENGINEERING FAILURE ANALYSIS
(2021)
Article
Engineering, Mechanical
Luca Susmel
Summary: This paper presents the reformulation of the Modified Wohler Curve Method to design notched components against constant/variable amplitude multiaxial fatigue loading using nominal stresses. The accuracy of this design methodology is validated against numerous experimental results from the literature, which strongly supports its effectiveness for assessing the multiaxial fatigue of notched structural components, even when fatigue strength reduction factors are estimated using standard formulas.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
A. Ince, G. Glinka
Summary: Several studies have indicated that fatigue crack growth is influenced by elastic-plastic strains and stresses localized near the crack tip. The distribution of stress and strain ahead of the crack tip is crucial in crack growth analysis of structural components. While numerical analysis methods can be used to compute local stresses and strains, they are costly and labor-intensive in engineering applications. Therefore, a new modeling framework based on approximation has been developed to calculate elastic-plastic stresses and strains ahead of a stationary crack tip, which has been verified through numerical finite element analysis data.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Luiz Carneiro, Qin Yu, Yanyao Jiang
Summary: The mechanical behavior and microstructure of a rolled AZ31B magnesium alloy under different ratios of axial and shear stress were experimentally investigated. The stress state significantly influenced the stress-strain responses and strain hardening rate. Different loading conditions resulted in variations in strength and ductility. Detailed twinning structures provided insights into the post-fracture texture and the mechanism behind the stress state effect.
INTERNATIONAL JOURNAL OF PLASTICITY
(2022)
Article
Chemistry, Physical
Tianqi Liu, Xinxin Qi, Xinhong Shi, Limin Gao, Tian Zhang, Jianyu Zhang
Summary: Multiaxial asynchronous fatigue experiments on 30CrMnSiA steel showed that frequency ratio affects fatigue crack initiation and propagation, with cracks propagating differently on stress planes and leading to different crack growth lengths for constant and asynchronous loading. Various fatigue life prediction models were compared, with the Bannantine-Socie cycle counting method, section critical plane criterion, and Palmgren-Miner's cumulative damage rule proving to be more applicable.
Article
Engineering, Mechanical
Daiyang Gao, Weixing Yao, Weidong Wen, Jie Huang
Summary: A spectral method for determining the critical plane and fatigue critical location under random vibration loadings for metallic materials is proposed, along with a multiaxial fatigue damage parameter for fatigue life evaluation. Experimental verification of the models through multiaxial random vibration fatigue tests showed good prediction capabilities for fatigue crack initiation locations and fatigue lives.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Materials Science, Characterization & Testing
Yiping Liao, Xiaoshan Liu, Guoqiu He, Zhiqiang Zhou, Yinfu Liu, Qigui Wang, Qiao He
Summary: The study investigated the effect of loading condition changes on the fatigue behavior and cyclic damage characteristics of A319 aluminum alloy through stress response curves, stress-strain hysteresis lines, fatigue fracture morphology, and dislocation substructure morphology in combination with material microstructure. The non-proportional hardening behavior shows strong loading path dependence, with greater fatigue plastic deformation and more severe fatigue damage in the circular and rhombic paths, resulting in a shorter fatigue life of A319 aluminum alloy. The axial directions under non-proportional multiaxial loading exhibit tensile and compressive asymmetric behavior, and the differences in loading paths result in different fatigue crack expansion modes. The non-proportional additional hardening behavior under different loading paths is closely related to the dislocation substructure, with higher dislocation density and strong interaction between dislocations and precipitation phases in the rhombic and circular paths.
Article
Engineering, Mechanical
Lei He, Le Xu, Takamoto Itoh
Summary: This study extends a fatigue life prediction approach for non-proportional loading to random amplitude loading waveforms and combines it with the rain-flow cycle counting method. Fatigue tests were conducted to validate the accuracy of the extended approach, and the reduction of fatigue limit under non-proportional loading was investigated through observations. The extended approach accurately evaluated the fatigue life under random non-proportional loading conditions.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Wei Zhang, Xuanming Zhang, Kaihao Zhang, Fei Liang, Xianxi Xia, Le Chang, Changyu Zhou
Summary: In this study, strain-controlled fatigue tests were conducted on P92 steel at 600 degrees C under uniaxial, multiaxial proportional, and multiaxial non-proportional loading conditions. The results indicate that the axial and shear stresses exhibit different responses to non-proportional loading, with proportional loading resulting in the shortest fatigue life when the strain ratio is small. The non-proportional loading induces accelerated cyclic softening in the axial direction while enhancing the shear stress.
MATERIALS CHARACTERIZATION
(2023)
Article
Mechanics
Chuanqi Zhu, Jun Zhao, Jiachao Xue, Feng Lin
Summary: This study investigates a three-dimensional crack growth model for rocks under stress, which can simulate crack growth and deformation characteristics. The research shows that the stress intensity factor at the crack tip increases with an increase in σ(1), promoting crack propagation, while it decreases with an increase in σ(2) and σ(3), inhibiting crack propagation.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Jing Li, Yuan-ying Qiu
Summary: In this research, a new life reduction index is proposed for predicting material's fatigue life considering non-proportional fatigue life reduction process. The index is based on the Fatemi-Socie damage parameter and has been validated using a large amount of experimental data, showing high prediction accuracy and robustness.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Engineering, Mechanical
R. Branco, P. A. Prates, J. D. Costa, J. A. Martins Ferreira, C. Capela, F. Berto
Summary: This study examines the notch fatigue behavior and crack initiation life estimation in maraging steel fabricated by laser beam powder bed fusion under multiaxial loading through experiments and numerical simulations. The results show that both simulation methods accurately predict the crack initiation sites, directions of crack growth, and fatigue life, with elastic-plastic predictions leading to smaller errors but slightly shifting to the non-conservative side.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Biochemistry & Molecular Biology
Rong Zhou, Lifei Niu, Jian Yin, Fangling Jiang, Yinlei Wang, Tongmin Zhao, Zhen Wu, Weimin Zhu
Summary: Waterlogging and heavy metal stress pose threats to crop growth. The effects of individual waterlogging and cadmium on tomato plants have been widely studied, but their combined effect is not well understood. This study compared the physiological and biochemical responses of two tomato genotypes under individual and combined waterlogging and cadmium stress, revealing different antioxidant enzyme regulation mechanisms.
Article
Engineering, Mechanical
Rita Dantas, Jose Correia, Grzegorz Lesiuk, Dariusz Rozumek, Shun-Peng Zhu, Abilio de Jesus, Luca Susmel, Filippo Berto
Summary: Multiaxial stresses are common in engineering structures, leading to multiaxial fatigue issues with different opinions and models for its description. Experimental research revealed that the multiscale approach by Dang Van and the Susmel model showed high accuracy and correlation in describing the fatigue behavior of S355 structural steel.
ENGINEERING FAILURE ANALYSIS
(2021)
Article
Engineering, Mechanical
Miloslav Kepka, Miloslav Kepka Jr, Radovan Minich
Summary: This paper focuses on the fatigue life evaluation of the bodywork of a new articulated electric (battery) bus. The findings resulted in recommendations to improve the operational reliability of a particular vehicle and provided challenges for future research.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
T. Dusautoir, B. Berthel, S. Fouvry, P. Matzen, K-D. Meck
Summary: This study investigates the impact of post-processing treatments on the fatigue limit of additive manufactured Ti-6Al-4V under stress gradients, with a focus on surface integrity.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Zhuofan Xia, Di Wu, Xiaochen Zhang, Jianqiu Wang, En -Hou Han
Summary: The study reveals the surface-initiated rolling contact fatigue (RCF) failure mechanism under heavy load and initial high roughness surface. The results indicate that precursor of collapsed morphology and nanocrystalline layer are the main factors causing lower RCF life with high roughness compared to low roughness surfaces. The spalling failure initiating from low roughness surface under heavy load is strongly dependent on surface plastic deformation.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Daniel Gren, Knut Andreas Meyer
Summary: Rolling contact loading can cause plastic deformation and fatigue cracks. Current rail standards do not consider the effect of plasticity on mechanical behavior. This study proposes a new method for evaluating the fatigue life of deformed material and finds that superimposed compressive axial loads can increase fatigue life.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
R. Kumar, S. Sanyal, J. Bhagyaraj, E. Hari Krishna, S. Mukherjee, K. Prasad, S. Mandal
Summary: This study investigates the thermomechanical fatigue (TMF) behavior of Timetal 834 alloy under different loading conditions. The results show that the alloy exhibits different cyclic hardening and softening responses at different strain amplitudes. The strain amplitude and phase angle have significant effects on the TMF life.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Kai Donnerbauer, Tobias Bill, Peter Starke, Ruth Acosta, Bharath Yerrapa, Christian Boller, Klaus Heckmann, Frank Walther
Summary: Given the aging of nuclear power plants, it is important to develop methods for evaluating the integrity of components and structures in nuclear engineering. Suitable nondestructive testing methods can detect material degradation and determine its fatigue life. This study utilized various NDT parameters and scanning electron microscopic methods to explore the relationship between microstructure evolution and NDT data.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Liuyong He, Jiang Zheng, Tianjiao Li, Houkun Zhou, Lihong Xia, Bin Jiang
Summary: This study quantitatively analyzed the effects of precipitates on the deformation mode, cracking mode, and mechanical behavior of WE54 magnesium alloy during low-cycle fatigue. It was found that precipitates promoted the activation of dislocation slip and suppressed the activation of twinning, affecting the cracking mode and mechanical behavior.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Xiangkang Zeng, Conghui Zhang, Wenguang Zhu, Mingliang Zhu, Tongguang Zhai, Xiaomei He, Kangkai Song, Zhuohang Xie
Summary: The cyclic deformation behaviors and damage mechanisms of pure Zr were investigated. The cyclic stress response was mainly influenced by substructure evolutions. Prismatic < a > dislocation slip was identified as the dominant deformation mechanism. Fatigue damage was not only influenced by the initial texture, but also other factors.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Jingyu Yang, Bingbing Li, Yiming Zheng, Gang Chen, Xu Chen
Summary: Heat treatment is used to improve the low-cycle fatigue performance of additive manufactured 316LN stainless steel. The heat-treated material demonstrates initially cyclic hardening followed by softening behavior, and shows a stronger resistance to crack propagation compared to the as-built material, resulting in a longer fatigue life.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Lang Zou, Dongfang Zeng, Xiong Chen, Jun Li, Hai Zhao, Liantao Lu
Summary: This study investigates the competitive relationship between fretting fatigue and plain fatigue in press-fitted railway axles. By changing the depth of the stress relief groove, the plain fatigue limit and fretting fatigue strength were tested. Detailed information was gathered, and an evaluation methodology integrating finite element simulation and the Modified Wohler Curve Method was established. The study concludes that the optimal groove depth, which balances the anti-fatigue capabilities, depends on the number of test cycles.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Davide Leonetti, Koji Kinoshita, Yukina Takai, Alain Nussbaumer
Summary: This paper investigates the fatigue behavior of non-load-carrying transverse welded steel attachments, including fatigue crack monitoring and fracture surface analysis under constant and variable amplitude loading. A procedure is proposed to obtain a Markov transition matrix based on the measured strain signal and to randomly resample the stress history for variable amplitude fatigue tests.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Zhe Zhang, Bing Yang, Yuedong Wang, Shoune Xiao
Summary: This paper presents a method for designing fatigue life prediction models with small sample sizes by handling limited sample data. The method integrates the equivalent structural stress method with the maximum likelihood estimation method and adds reliability verification, resulting in enhanced goodness of fit, stability, and optimized sample quantity.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Cooper K. Hansen, Gary F. Whelan, Jacob D. Hochhalter
Summary: This paper presents a method to address the computational demand issue of computing FIPs using CPFEM by developing an interpretable machine learning model. Genetic programming is used to evolve interpretable expressions of FIPs from microstructure features, and these models can serve as efficient substitutes for CPFEM and be easily integrated into engineering workflows.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Luca Susmel
Summary: This paper discusses the problem of estimating notch fatigue limits using machine learning. The results show that machine learning is a promising approach for designing notched components against fatigue. The accuracy in estimating the fatigue limit can be increased by increasing the size and quality of the calibration dataset, as well as including additional input features.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Kefeng Gao, Guoqi Tan, Yanyan Liu, Qiang Wang, Qian Tang, Xuegang Wang, Qiqiang Duan, Zengqian Liu, Zhe Yi, Zhefeng Zhang
Summary: Bioinspired architectures have significant effects on material enhancement. This study investigates the fatigue properties of bioinspired ceramic-polymer composites and natural nacre, revealing the close relationship between architectural types, orientations, fatigue performance, and damage mechanisms.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)