Utilizing a novel lattice orientation based stress characterization method to study stress fields of shear bands

摘要

A new framework for evaluating stress fields from distributions of crystallographic orientation is presented. The framework employs the kinematics of crystal plasticity and field dislocation mechanics to connect measured lattice orientation, crystallographic slip, and geometrically necessary dislocations to recover the elastic deformation field present, and subsequently determine the stress using a finite-element scheme. As a demonstration of the framework's utility, stress fields generated by the formation of shear bands in a copper single crystal are studied, including how these bands' stress fields drive secondary slip. The results indicate that small amounts of secondary slip shielded stresses produced by the shear bands and that the bands were oriented in a low-energy configuration, stabilizing their structure. (C) 2019 Elsevier Ltd. All rights reserved.