摘要
平板内开孔产生的应力集中对低周疲劳载荷下的裂纹板在裂纹扩展阶段具有一定的影响,同时随着裂纹长度增加影响逐渐降低.为了定量分析这一过程中裂尖应力-应变场的演化,探讨其影响机理,文中以数值模拟为基础,利用弹塑性断裂力学,结合不同应力比下的累积塑性应变探究其相互作用.研究结果表明:孔边应力集中导致塑性应变累积程度增强,裂纹闭合效应减弱,裂尖残余压应力场降低,从而影响裂纹扩展速率.
The stress concentration caused by the opening in the flat plate has a certain influence on the cracked plate under low cycle fatigue load in the crack propagation stage,and the influence gradually decreases with the increase of crack length.In order to quantitatively analyze the evolution of stress-strain field at crack tip in this process and explore its influencing mechanism,elastic-plastic fracture mechanics and cumulative plastic strain under different stress ratios were used to explore their interaction.The results show that the stress concentration at the edge of the hole leads to the increase of plastic strain accumulation,the weakening of crack closure effect,and the decrease of residual compressive stress field at the crack tip,thus affecting the crack propagation rate.
作者
孙辉
杨平
SUN Hui;YANG Ping(School of Naval Architecture,Ocean and Energy Power Engineering,Wuhan University of Technology,Wuhan 430063,China)
出处
《武汉理工大学学报（交通科学与工程版）》
2022年第4期654-658,共5页
Journal of Wuhan University of Technology（Transportation Science & Engineering）
基金
国家自然科学基金(51779198)。
关键词
累积塑性
裂纹扩展
低周疲劳
孔洞
裂纹闭合效应
accumulative plasticity
crack propagation
low cycle fatigue
perforated hole
crack closure effect
