The characteristics of J-integral under biaxial stressing

Although it is recognised that biaxial or triaxial stressing can affect the fracture conditions and stress/strain held of a cracked body, insufficient attention has been paid to how biaxial or triaxial stresses affects the pr operties of the J-integral. In this paper, two-dimensional incremental and three-dimensional incremental theory elastic-plastic finite element program s have been adopted to analyse the effect of biaxial stressing on J-integra l of a finite plate containing a through-thickness crack and subjected to b iaxial stresses. Constitutive equations describing the material behaviour w ere chosen as: (i) the practical stress strain relation of 16MnR; (ii) modi fied yielding plateau stress strain relationship of 16MnR; and (iii) Ramber g-Osgood representation. The finite element analysis results show that the properties and values of J-integral under biaxial stressing can be signific antly different from those under uniaxial stressing. Attention must, theref ore, be paid to J-integral calculations when considering it as a fracture p arameter to analyse multi-stressing situations. (C) 2000 Elsevier Science L td. All rights reserved.