Relationship between current density and microstructure of Ti60 alloy during multi-physical field coupling process

Abstract

The effects of pulse current on recrystallization, dislocation density, deformation coordination, and texture evolution in Ti60 alloy were investigated through an electro-assisted tensile test under five different current densities. The results demonstrate that increasing current density significantly promotes atomic diffusion and dislocation annihilation, facilitating grain boundary migration and recrystallization. Enhanced pulse currents improve deformation coordination and overall formability of the Ti60 alloy. At a current density of 30 A/mm², two dominant textures are observed, and the presence of multiple preferred planes at this level indicates superior plasticity compared to other conditions. Moreover, the Joule heating effect below 30 A/mm² primarily activates the basal <a> slip system as the main slip mechanism, while the athermal effect above 30 A/mm² favors the prismatic <a> slip system as the dominant slip mechanism. Among the tested conditions, 30 A/mm² achieves the most favorable balance between microstructural and mechanical performance, making it the optimal current density in this study.