边界元法计算浅表面裂纹应力强度因子

Evaluation of the stress intensity factor of the crack close to the surface by the boundary element method

文章在常规边界元法中引入几乎奇异积分的解析算法,来计算浅表面裂纹的应力强度因子,并给出了一个二维平板中有浅表面裂纹的算例。处理了几乎奇异积分的边界元法可以有效分析离表面仅为0.5μm的浅表面裂纹。结果显示,随着距表面距离的减小,裂纹的应力强度因子收敛于常数,但其大小与无限大板中裂纹的应力强度因子有很大差别。

The analytic algorithm of nearly singular integrals is introduced into the conventional boundary element method（BEM） to calculate the stress intensity factors （SIF） of the crack very close to the surface. A crack under the subsurface of a plate is numerically tested as an example. The presented BEM can successfully evaluate the SIF even when the distance between the crack and the surface is 0. 5μm. The results show that the SIF converge to a constant as the distance from the crack to the surface is reduced. However, there is a great difference between the SIF of the crack close to the surface and the SIF of the crack in an infinite plate.