The Effect of Welding Residual Stress Upon Brittle Fracture Propagation (Report II)

Abstract

In the previous report the authors described the method of calculating the strain energy release rate when brittle crack propagates in residual stress field, but the present paper deals with the application of such calculation method to various experimental values.In other words, 1) By means of graphic algebra the strain energy release rate was sought from the actually measured residual stress field.2) The plastic surface energies at the times of the initiation and arrest of brittle fracture were sought and the values of 0.5 and 0.1kg-m/cm2, respectively, were obtained.3) Studies were made about the effect of notch shape upon the brittle fracture conditions.Moreover, the stress condition near the notch root was measured and discussed.