The effects of load condition on void coalescence in FCC single crystals

Abstract

To investigate the effects of load condition on void coalescence in FCC crystals, void coalescence under constant strain control was studied by using three-dimensional crystal plasticity finite element method, which was implemented with rate dependent crystal plasticity theory as user material subroutine. By comparison the width of inter-void ligament in single crystals, significant effects of load condition on void coalescence were revealed: (1) Crystallographic orientation plays a role in void coalescence, and the role is different under various load conditions. (2) The deformation is localized around voids under triaxial applied strain load condition, and the slip systems in soft orientation are easy to be activated, so voids in soft orientation grains tend to coalesce much easier than that in hard orientation, and the void growth direction has only a minor role in influencing the coalescence effect for different crystallographic orientations. (3) Under low biaxial applied strain load condition, the deformation localization is not serious, and the global deformation of soft orientation is homogeneous, so soft orientation shows less coalescence effect in general.