Yan Jinfeng, Meng Wenjun, Chen Zhi, Guo Hong, Yan Xianguo
School of Mechanical Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, China.
China International Engineering Consulting Corporation, Ltd, Beijing 100048, China.
Materials (Basel). 2020 Apr 8;13(7):1732. doi: 10.3390/ma13071732.
Numerical study was performed to determine the fatigue limit of metallic glass under tension-compression cyclic loading. A revised free-volume theory which considers the hydrostatic stress was utilized to make the predictions. Systematical simulations showed that a higher strain amplitude is prone to making the sample completely damaged earlier. However, lower strain fluctuations could result in a longer fatigue life. Shear banding evolution history described by free-volume localization could reasonably explain the mechanical responses of different samples. In addition, compressive loading could give rise to a higher stress than that under tensile loading because of hydrostatic stress contribution. In the end, a correlation between fatigue life and applied strain amplitude was plotted which could supply a guidance for designing the engineering application of metallic glass under periodic loading.
进行了数值研究以确定金属玻璃在拉压循环载荷下的疲劳极限。利用一种考虑静水压力的修正自由体积理论进行预测。系统模拟表明,较高的应变幅值更容易使样品更早地完全损坏。然而,较低的应变波动可能导致更长的疲劳寿命。由自由体积局部化描述的剪切带演化历史可以合理地解释不同样品的力学响应。此外,由于静水压力的贡献,压缩载荷会产生比拉伸载荷更高的应力。最后,绘制了疲劳寿命与施加应变幅值之间的相关性,可为金属玻璃在周期性载荷下的工程应用设计提供指导。