A yield function for single crystals containing voids

A yield function for single crystals containing voids has been developed based on a variational approach. This first yield function is phenomenologically extended by modifying the dependence on the mean stress and introducing three adjustable parameters. Unit cell finite element calculations are performed for various stress triaxiality ratios, main loading directions and porosity levels in the case of a perfectly plastic FCC single crystal. The three model parameters are adjusted on the unit cell calculations so that a very good agreement between simulation results and the proposed model is obtained.