Article
Green & Sustainable Science & Technology
Josip Brnic, Marino Brcic, Sebastian Balos, Goran Vukelic, Sanjin Krscanski, Mladomir Milutinovic, Miroslav Dramicanin
Summary: The paper presents experimental investigations on the mechanical properties of unalloyed high quality steel S235JRC + C (1.0122) under high temperature, creep, and mechanical fatigue conditions. The material's response at different temperatures is shown through engineering stress-strain diagrams, creep behavior is depicted using creep curves, and a fatigue diagram is constructed based on mechanical fatigue tests. The study determines the tensile strength, fatigue limit, and creep resistance of the material under different conditions.
Article
Engineering, Chemical
Sebastian Jobst, Markus Stommel
Summary: Material and lifetime modeling of silicone adhesives is crucial in the building and automotive industry. By characterizing an elastomeric silicone adhesive with different thermomechanical methods, key material parameters for lifetime prediction were identified. It was found that frequency and temperature dependence for strains beyond a certain threshold were negligible, making the time-temperature superposition principle ineffective for extrapolation.
INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
(2022)
Article
Engineering, Mechanical
Ning Zhang, Shuo Guo, Guoning He, Bo Jiang, Leyu Zhou, Yong Chen, Yazheng Liu
Summary: This paper analyzed the reasons for the fatigue failure of carburized 20MnCr5 gears and proposed an optimized carburizing process to improve the fatigue life.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Marine
Hai-Yang Liu, Xiao-Hua Huang, Guo-Liang Pang, Tai-Ping Yuan, Yu Hu, Si Yuan
Summary: This study evaluates the failure risk of the fish cage by analyzing the yield and fatigue phenomena of the floating structure under wave loads. The results show that the C80 fails when the overall horizontal load reaches 3000 kN or the wave height is 23.4 m. The main failure areas are the mooring points, with stress concentration occurring at the cracked parts. Enhancing the specifications and increasing the circular curvature and assembling clearances can provide guidelines for the structural design and optimization of the HDPE super large fish cage.
Review
Geochemistry & Geophysics
Xueliang Li, Yu Wang, Shuo Xu, Haonan Yang, Bo Li
Summary: In rock engineering in cold regions, natural fractures are susceptible to repeated freeze-thaw weathering, which can lead to rock engineering instability and geological hazards. Laboratory tests show that natural fractures impact fatigue strength, lifetime, and energy dissipation of rock. The dissipated energy decreases with the increase of natural fracture volume and presents a slow-fast pattern with cycle number growth.
Article
Nuclear Science & Technology
Wenhai Guan, Hyoseong Gwon, Takanori Hirose, Hisashi Tanigawa, Yoshinori Kawamura, Motoki Nakajima, Takashi Nozawa
Summary: This study conducted creep-fatigue tests on F82H at 823 K, comparing tension holding with compression holding. It was found that CF damages were within the damage envelope of Grade 91 in ASME NH, indicating the potential resistance of the cylindrical WCCB TBM design under ITER thermo-mechanical load conditions.
FUSION ENGINEERING AND DESIGN
(2021)
Article
Materials Science, Characterization & Testing
Britta Schramm, Deborah Weiss
Summary: Strength calculation and fracture mechanics are essential for reliable, strength-compliant and fracture-resistant design, as well as prevention of damage cases. This paper explains the general procedure of fracture mechanical evaluation for fatigue cracks and provides detailed explanations of fracture mechanical fundamentals for stress intensity factor calculation and experimental determination of material parameters. Fracture mechanical evaluation is conducted for different materials and selected crack problems, with a focus on material HCT590X being investigated by TRR285.
Article
Engineering, Geological
Yu Wang, Xuefeng Yi, Dayu Long, Yingjie Xia, Peng Li, Meifeng Cai
Summary: This study investigates the effect of disturbed stress amplitude on the failure and energy evolution characteristics of the rock-backfill composite structure in underground mine stopes. The results show that specimens with low stress disturbance have the longest lifetime, while volumetric strain increases with increasing disturbed stress amplitude. More energy is consumed and severe cyclic loading induced damage occurs for samples subjected to high stress disturbance. CT images reveal the cracking pattern and failure characteristics of the surrounding rock and backfill material. The backfill material plays a crucial role in preventing spalling and collapse.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Mechanics
Lulu Liu, Xin Wang, Zhishen Wu, Thomas Keller
Summary: The study found that the tension-tension fatigue behavior of ductile adhesively-bonded double-lap FRP joints was influenced by cyclic creep, with damage acceleration mainly caused by fatigue at high load levels and by creep and self-generated temperature at low load levels.
COMPOSITE STRUCTURES
(2021)
Article
Engineering, Mechanical
Michal Bartosak
Summary: In this article, machine learning is used to predict the lifetime under isothermal low-cycle fatigue and thermo-mechanical fatigue loading. Two machine learning based approaches are demonstrated using a fatigue and fatigue-creep dataset. The results show a good correlation between the experiment and the prediction, suggesting that machine learning based damage models can reasonably predict the lifetime under complex thermo-mechanical loading.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Michal Bartosak, Jakub Horvath, Zdenek Pitrmuc, Marie Rohlova
Summary: The phase angle in TMF tests has a significant influence on the dominant damage mechanism and observed lifetime. A modified damage model has been proposed to account for the effect of the phase angle.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Chemistry, Physical
Xingkai Wang, Wansheng Wei, Yong Niu, Caichu Xia, Leibo Song, Guansheng Han, Zheming Zhu
Summary: This study investigates the instantaneous mechanical behavior, failure characteristics, and creep behavior of dolomitic limestone under different confining pressures. The results show that as the confining pressure increases, the rock transitions from brittleness to ductility and the stress drops during the post-peak stage decelerate. The confining pressure also affects the cracking deformation during the pre-peak stage. Additionally, the confining pressure has an impact on the threshold values and a higher confining pressure corresponds to a greater threshold value.
Article
Materials Science, Multidisciplinary
Guoying Sui, Zhenqiang Wang, Fengchun Jiang, Chengzhi Zhao, Jiandong Wang
Summary: The motivation of this work is to investigate the cyclic deformation behaviors of 42CrMo steel under uniaxial stress-controlled cyclic-loading. The study reveals that the cyclic deformation is positively correlated with increases in mean stress and stress amplitude, while the increase in loading frequency inhibits the cyclic accumulation deformation.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2023)
Article
Engineering, Mechanical
Christos Skamniotis, Alan C. F. Cocks
Summary: The study establishes the connections between elastic-inelastic analyses and between material phenomena-PDL geometry, indicating pathways for improving life. Fatigue crack initiation at film holes occurs with a low number of cycles due to excessive plasticity.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Engineering, Mechanical
Qingtong Wang, Bingbing Li, Jingwei Zhao, Takamoto Itoh, Xu Chen
Summary: Isothermal and thermomechanical fatigue tests were performed with different tension dwell times, and the cyclic stress response and stress relaxation behavior were analyzed using TEM and EBSD. The results showed that fatigue was the dominant mechanism for crack initiation and propagation in all creep-IF tests, leading to specimen fracture. However, in creep-TMF tests, when the dwell time increased to 1800 s, the dominant damage mechanism shifted to creep-fatigue interaction, resulting in intergranular fracture mode and a significantly shorter life. Additionally, a life prediction model based on tension strain energy was proposed.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)