Surface Crack Propagation Analysis under Residual Stress Field

Abstract

Stress intensity factors due to surface crack propagation were analysed by using the influence function method and inherent strain analysis of the residual stress fields caused by welding. The initial residual stress in a plate with a welded butt joint was calculated by using inherent strain analysis, and the redistribution of residual stress and the stress intensity factor due to crack propagation were analysed as changes in the structure’s shape. The stress intensity factor was also calculated by using an influence function database. The stress intensity factor in the residual stress fields due to crack propagation obtained by using inherent strain analysis completely agreed with that obtained by using the influence function method. The results of the crack propagation analysis were compared with the experimental results of a fatigue test. It was validated that both the inherent strain analysis and the influence function method were efficient for analysing stress intensity factors in residual stress fields caused by welding.