裂纹钢丝的应力与疲劳寿命分析

Stress and fatigue life analysis of cracked steel wire

本文利用疲劳应力估算法研究含裂纹的钢丝疲劳寿命。通过Ansys Workbench模拟现实工况下绞合钢丝受力状态,研究裂纹扩展过程及裂纹处的应力曲线。结果表明:因工况受力的钢丝裂纹会在宽度及深度这两个自由度拓宽加深并其前缘会出现应力集中现象。同时,利用N-node对钢丝绳的疲劳寿命进行仿真分析,得到裂纹前缘处的"蝶形"损斑及裂纹节点处的寿命。结果表明:裂纹前缘处的等效应力与疲劳损伤呈正相关,与疲劳寿命呈负相关。仿真得出的裂纹钢丝的应力特征与疲劳寿命的关系,对及时修补钢丝缺陷让其继续保持机械性能有极大意义。

The fatigue life of steel wire with crack is studied by fatigue stress estimation.Ansys Workbench is used to simulate the stress state of stranded steel wire under real working conditions,and the crack growth process and stress curve at the crack were studied.The results show that the width and depth of the two degrees of freedom of the crack increase and deepen,and the stress concentration occurs at the leading edge of the crack.At the same time,N-node is used to simulate and analyze the fatigue life of the wire rope,and the "butterfly-shaped" damage and the life of the crack at the front edge were obtained.The results show that the equivalent stress at the crack front is positively correlated with fatigue damage and negatively correlated with fatigue life.The relationship between stress characteristics and fatigue life of cracked steel wire obtained by simulation is of great significance for repairing defects of steel wire in time to keep its mechanical properties.