Article
Engineering, Mechanical
Y. Murakami, M. Endo
Summary: A prediction method for S-N curves without fatigue tests is proposed in this study. The method is based on the small crack (m*) growth model and predicts S-N curves for various materials. The predicted curves are compared with experimental data, showing good agreement for conservative predictions.
ENGINEERING FAILURE ANALYSIS
(2023)
Article
Engineering, Mechanical
Tsuyoshi Miyakoshi, Takeru Atsumi, Kensuke Kosugi, Atsushi Hosoi, Terumasa Tsuda, Hiroyuki Kawada
Summary: This paper investigates the transverse crack initiation behaviors of carbon fiber-reinforced plastics (CFRPs) in the high-cycle and very high cycle regimes. The fatigue behavior of cross-ply CFRP laminates formed with T800S/2592 prepreg was studied by using an ultrasonic fatigue testing system. The results show that the slope of the S-N diagram for transverse crack initiation decreases linearly within a certain number of cycles and levels off after a certain number of cycles, and no cracks were observed under a certain stress.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Nanoscience & Nanotechnology
Alice Cervellon, Chris J. Torbet, Tresa M. Pollock
Summary: The anisotropic fatigue properties of three Ni-based SX superalloys were investigated in the very high cycle fatigue regime. The [111] orientation showed higher fatigue lives at high stresses but lower fatigue lives at very low stresses. The resolved shear stress on the octahedral slip systems and the pseudo-cube slip in the matrix were identified as the main reasons for the anisotropy effect.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Xiaolu Gui, Guhui Gao, Baifeng An, R. D. K. Misra, Bingzhe Bai
Summary: The study investigated the effects of inclusion size and microstructural features on HCF/VHCF in a B/M steel. It was found that fatigue crack initiation was mainly influenced by inclusions, with the majority of fatigue life consumed by the crack initiation process regardless of the source of the crack. The ratio of fatigue crack initiation life to total fatigue life exhibited a wide scatter due to variations in the B/M hierarchical structure within individual prior austenite grains when cracks initiated from sub-surface microstructure.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Engineering, Mechanical
Tao Gao, Hongqian Xue, Zhidan Sun, Delphine Retraint, Yanli He
Summary: The fatigue behavior and damage mechanisms of a Ti-8Al-1Mo-1V alloy were investigated in the very high cycle fatigue (VHCF) regime. It was found that the crack initiation area is characterized by nano-marking facets and flat facets induced by slip activity. The large scatter in fatigue life can be attributed to slip inhomogeneity.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Engineering, Mechanical
Noelle Easter C. Co, James T. Burns
Summary: The fatigue resistance of aerospace structures is affected by corrosion damage. The formation of fatigue cracks is influenced by the micro-scale corrosion morphologies and underlying microstructure. A modest correlation was found between the initiation of fatigue cracks and grains with high misorientation angles with respect to adjacent grains.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Materials Science, Multidisciplinary
Jingyu Sun, Guian Qian, Jianghua Li, Ruiyang Li, Zhimo Jian, Youshi Hong, Filippo Berto
Summary: Currently, there is no systematic approach to simulate the microstructure sensitive crack initiation and propagation process in very-high-cycle fatigue. In this study, a computational framework combining crystal plasticity and cohesive zone model is developed to simulate the defect-induced short crack growth in an additively manufactured AlSi10Mg alloy. The framework can control the crack growth rate and the proportion of crack initiation damage in the total damage. An acceleration strategy is proposed to improve the computational efficiency for very-high-cycle fatigue. Experimental observations and simulation results show good agreement.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Engineering, Mechanical
Yukitaka Murakami, Toshio Takagi, Kentaro Wada, Hisao Matsunaga
Summary: This paper elucidates the essential structure of the S-N curve based on fatigue life and material limit prediction methods containing defects, and discusses the extended application of this method to step loading and variable amplitude loading. The applicability of Miner's rule is also discussed from the perspective of continuous decrease in fatigue limit with number of stress cycles and crack growth.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Engineering, Mechanical
Xue Li, Yajun Dai, Xiangyu Wang, Yongjie Liu, Yao Chen, Chong Wang, Hong Zhang, Lang Li, Hanqing Liu, Chao He, Qingyuan Wang
Summary: This study investigates the effect of local microstructure on the crack initiation behavior of a super martensitic stainless steel in the very high cycle fatigue regime. Results show that non-inclusion-induced crack initiation dominates, with fatigue cracks initiating from martensite boundaries forming slip areas. The size and orientation of martensite lath affect the morphology of slip areas but have limited influence on the formation of fine granular areas at the fracture surface.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Weiqian Chi, Gen Li, Wenjing Wang, Chengqi Sun
Summary: This study investigates the very high cycle fatigue behavior of additively manufactured Ti-6Al-4V material under different stress ratios. The fracture surface analysis reveals the presence of a fine granular area (FGA) with discontinuous regions of nanograins in the crack initiation and early growth region. The crack growth rate in the FGA can be used to predict the fatigue life.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Jun Guo, Aimin Zhao, Maosheng Yang
Summary: The fatigue properties of M50 bearing steel under high cycle fatigue at room temperature were investigated. The fatigue cracks in M50 bearing steel primarily originated from MgO-Al2O3 inclusions and MC/M2C primary carbides. The voids were initiated by debonding of inclusions from the matrix and cracking of primary carbides under cyclic loading. Small cracks initiated perpendicular to the tensile stress and propagated at a speed of 8.81 x 10-10 m/cycle in the fine granular area (FGA). A fatigue crack nucleation model and fatigue life model were established based on stress intensity factor range, defect properties, and number of cycles.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Fulin Liu, Haotian Peng, Yongjie Liu, Chong Wang, Qingyuan Wang, Yao Chen
Summary: The fatigue behavior of titanium alloy with different stress ratios was studied at 400 degrees C in the VHCF regime. The initiation of cracks depends on the formation of facets, which is related to the maximum shear stress. The formation of facets is induced by basal or prismatic slips with a high Schmid factor inside alpha(p) grains. The morphology of alpha(p) grains affects the initiation of cracks. High-density geometrically necessary dislocations (GNDs) accumulate along with the slips and form subgrain boundaries (sub-GBs) within alpha(p) grains. With cyclic loading, the created sub-GBs further form facets, initiating microcracks.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Materials Science, Multidisciplinary
Zhi Qin, Bin Li, Chen Chen, Tianyue Chen, Rui Chen, Han Zhang, Hongqian Xue, Changfeng Yao, Liang Tan
Summary: The study investigated the high cycle and very high cycle fatigue behavior of the GH4169 superalloy. The results showed that failures in different fatigue regimes had different initiations, and significant strain localization occurred at the twin boundaries of the material under fatigue cyclic loading.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Tao Gao, Xu Zhao, Hongqian Xue, Zhidan Sun
Summary: The fracture surface characteristics and micromechanisms of fish-eye crack initiation in a Ti-6Al-4V alloy under VHCF loading were investigated. The crack initiation area exhibited ragged-like mountains, dimples, and various irregular rods/particles, grooves, and microvoids. These characteristics were primarily attributed to the nucleation and coalescence of microvoids and grooves at the alpha(s)/beta(r) interface inside the beta(trans). The beta(trans) played a dominant role in the fish-eye crack initiation and early propagation process.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Engineering, Mechanical
Xue Li, Chao He, Xiangyu Wang, Yao Chen, Chong Wang, Hong Zhang, Lang Li, Yongjie Liu, Qingyuan Wang
Summary: This study investigated the behavior and crack initiation mechanism of super martensitic stainless steel under very-high-cycle fatigue at elevated temperature. The cracks in this condition initiated from the surface and formed a fine granular area. This area consisted of an initiation site, a smooth region, and an annular continuous fine granular area. The fine granular area formed in the peaks and valleys of local microstructures, while the smooth regions connected these peaks and valleys dominated by shear stress.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Nanoscience & Nanotechnology
Shu-Xin Li, Peng-Cheng Zhao, Yan-Ni He, Shu-Rong Yu
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2016)
Retraction
Engineering, Mechanical
Shu-Xin Li, Peng-Cheng Zhao, Yun-Shuai Su, Shu-Rong Yu
TRIBOLOGY INTERNATIONAL
(2016)
Article
Materials Science, Multidisciplinary
P. Zhao, B. Chen, J. Kelleher, G. Yuan, B. Guan, X. Zhang, S. Tu
Article
Materials Science, Multidisciplinary
P. -C. Zhao, B. Chen, Z. -G. Zheng, B. Guan, X. -C. Zhang, S. -T. Tu
Summary: The post-dynamic recrystallization behavior of ultrafine-grained cp-Ti was investigated under different temperatures and deformation rates. Recrystallization and grain growth were confirmed to occur due to annealing and fatigue at room temperature. The fatigue-induced grain growth was found to be intriguing, with noticeable misorientation aggregation and increased grain size observed.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2021)
Article
Engineering, Mechanical
Run-Zi Wang, Lv-Yi Cheng, Shun-Peng Zhu, Peng-Cheng Zhao, Hideo Miura, Xian-Cheng Zhang, Shan-Tung Tu
Summary: A large number of strain-controlled creep-fatigue tests were conducted at 650 degrees Celsius on nickel-based forged GH4169 superalloy under wide loading waveforms. Post-test examinations included comprehensive characterizations using scanning electron microscope, electron backscatter diffraction, and transmission electron microscope. The study found that strain ratio has little influence on creep-fatigue damage degrees, while dwell time causes noticeable changes to damage progressions.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Materials Science, Multidisciplinary
Peng-Cheng Zhao, Guang-Jian Yuan, Run-Zi Wang, Bo Guan, Yun-Fei Jia, Xian-Cheng Zhang, Shan-Tung Tu
Summary: The microstructural evolution and mechanical properties of ultrafine-grained CP-Ti were systematically examined after large-volume equal channel angular pressing (L-ECAP) and multi-directional forging (MDF). The grain size distribution conformed to lognormal distribution, with iron impurities promoting recrystallization during L-ECAP. The strain hardening rate of CP-Ti increased with decreasing grain size, while the continuous strain hardening ability decreased.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Proceedings Paper
Engineering, Mechanical
Guang-Jian Yuan, Peng-Cheng Zhao, Xian-Cheng Zhang, Shan-Tung Tu, Xiao-Gang Wang, Cheng-Cheng Zhang
MECHANICAL FATIGUE OF METALS: EXPERIMENTAL AND SIMULATION PERSPECTIVES
(2019)