3-DIMENSIONAL ANALYSES OF INTERFACE CRACK FRONT FIELDS

Three-dimensional finite element computation is performed for a through edge crack lying on an interface between an elastic plastic material and a perfectly rigid substrate. The modified Gurson model suggested by Tvergaard and Needleman is used in the calculation. The distributions of stresses and microvoid volume fraction in an edge-cracked specimen subjected to a remote tensile stress are presented. It is found that the severe stress and void concentrations occur in the corner where the crack front runs into the free surface. The maximum microvoid volume fraction appears on the free surface when the remote stress is low, but appears inside the free surface at the higher remote stress.