Elastic-plastic analysis of combined mode I, II and III crack-tip fields under small-scale yielding conditions (Q1210633)

Stationary cracks in power-law hardening materials are investigated. By using a finite element technique, asymptotic angular stress solutions are obtained for combined mode I and II perturbed from mode III. These solutions reveal the same stress singularities as those of pure mode III, and the order of crack-tip-stress singularities varies smoothly with changing mode mixity. A full-field finite element computation is used to investigate the small-scale yielding near-tip fields. Effective in-plane and out-of-plane shear stresses are introduced to quantify the in-plane and the out-of-plane plastic shear at different orientation. The full- field solutions corroborate that the singularities of the in-plane stresses and of the out-of-plane stresses vary smoothly with mode mixity.