准静载作用下弹塑性微弯裂纹张开位移

Research on CTOD of slightly curved extension elasticity-plasticity crack under quasi static loads

综合考虑了准静态作用应力,塑性区域边界上正应力与剪应力,利用二阶摄动方法与卡氏定理计算了弯曲裂纹尖端的张开位移。研究了在不同的准静载荷条件下弹塑性弯曲延伸裂纹尖端张开位移随着弯曲裂纹形状参数的变化而变化的规律。研究表明,当初始裂纹长度与弯曲路径的形状参数为定值时,弯曲延伸裂纹尖端张开位移大小随外载荷的增大而增大,且增加的趋势非常剧烈。

In this article, CTOD of elastic-plastic curved extension crack under quasi static loads is mainly studied, and curved crack tip opening displacement is calculated as a practical application of a second order perturbation method and KA’s theorem, where the effects of the quasi static loads, the applied stresses, and the normal and shear stresses, on the boundaries of plasticity area, are synthetically taken into considerations. A regular pattern of variations of CTOD of elastic-plastic curved extension crack with the variations of shape parameters under different quasi static loads is mainly studied.