Limits of Applicability of Models Predicting Initiation of Crack Growth for Surface Cracks

摘要

In predicting the integrity of a structural component containing surface cracks, the general approach for plane strain, linear-elastic conditions is to use the plane strain fracture toughness and appropriate analytical solutions. The general adequacy of this approach has been verified although the accuracy has not been quantified for many conditions. For conditions of increased ductility (elastic-plastic, E/P, and plastic) it is possible to measure the J-integral associated with initiation of crack growth and the tearing modulus. There are no generally accepted analytical solutions for predicting the behavior of a generic surface crack. This paper summarizes results obtained by comparing predicted stresses with experimentally determined stresses for crack initiation and crack penetration of the wall thickness. Test data were generated for A710 and Ti-15-3 for elastic conditions and A710 for E/P and plastic conditions. (ERA citation 11:007446)