Finite Element Analysis of a Cracked Body with Residual Stresses

Abstract

As the J-integral displays the path-dependency in the case of residual stresses, the Ĵ-integral proposed by Sakata et al. was applied to investigate the residual stress field in this paper. The Ĵ-integral for a cracked body with residual stresses was analyzed by means of numerical calculation. Two types of the distributions of the residual stresses are considered here for the Ĵ-integral analysis. One is the surface residual stresses, the other is residual stresses distributed throughout the whole volume. In the latter case, the residual stresses caused by non-uniform plastic deformation (the unloading residual stresses) and the welding residual stresses are adopted. The elastic-plastic finite element method is applied in the numerical calculation. The results obtained show that the Ĵ-integral has the property of path independence in the cases of existing residual stresses.