An approximate yield criterion for porous single crystals

This study is devoted to the derivation of an approximate yield function for voided single crystals deforming by crystallographic slip. By making use of a regularized form of the Schmid law and solving approximately the hydrostatic case with a limit-analysis calculation, a Gurson-type yield criterion is proposed. It is obtained by a heuristic extension of existing limit-analysis results for a matrix obeying a quadratic Hill-type criterion. The proposed yield function is successfully compared with numerical results from the literature for face-centered cubic crystals.