Crystal Plasticity Analysis of Change in Active Slip Systems of α-Phase of Ti-6Al-4V Alloy under Cyclic Loading

Abstract

In this paper, we investigated changes in active slip systems of α-phase of Ti-6Al-4V alloy under a cyclic plastic loading using a crystal plasticity finite element method. In the analyses, a bicrystal model was employed, and the crystallographic orientations were set so as that prismatic <a> or basal slip system was the primary slip system in each grain. The results showed that there was a mechanism where the basal slip systems could reach the stage of activation under the cyclic plastic loading even though the condition was that the prismatic <a> slips initially operate. The reason for the activity changes was due to the changes in the incompatibility between the grains by the work hardening, and the effect of the incompatibility on activities of slip systems appeared even in the perpendicular arrangements of the grains to the loading direction.