A family of plane strain crack tip stress fields for interface cracks in strength-mismatched elastic-perfectly plastic solids

Asymptotic crack tip stress fields are developed for a plane strain crack l ocated on the interface between two incompressible, elastic-perfectly plast ic solids, with matching elastic properties, but mismatched yield strengths . The complete range of normal versus shear tractions on the interface at t he crack tip is analyzed. In the limit as the yield strength mismatch vanis hes the asymptotic stress fields for the interface crack approach establish ed crack tip fields for homogeneous bodies. The crack tip stress fields are assembled from combinations of centered fans, constant stress sectors and elastic sectors. All the stresses within each material region are continuou s while traction continuity is maintained across the interface. These asymp totic stress fields are verified by comparison with small-scale yielding fi nite element solutions obtained for various remote load mixity using bounda ry layer formulations (Rice, 1967). (C) 1999 Elsevier Science Ltd. All righ ts reserved.