Fracture initiation in a single crystal copper edge-crack specimen for various crystallographic orientations

Abstract

The motivation of the present study entails the determination of fracture initiation of a single crystal copper edge-crack specimen subjected to tensile load by considering the influence of crystallographic anisotropy, strain hardening and damage accumulation. To accomplish the purpose of this study, a damage criterion coupled with crystal plasticity finite element method was used to determine material softening after the peak load. Damage evolution was chosen as the function of maximum shear strain within the crystal plasticity framework. Coupled with a damage criterion, the crystal plasticity model was used to reproduce the stress-strain responses of copper single crystals until failure. The model was then applied to assess damage evaluation near crack-tip of a single crystal copper edge-crack specimen along two crystallographic orientations of tensile loading directions. The analysis abetted to predict fracture initiation (J-initiation) of a crack lying along various crystallographic orientations, while keeping the loading direction orientation identical in all the cases. The methodology presented here has the scope to analyze single crystal complex structures with cracks subjected to loading along various crystallographic orientations.