Effects of deformation conditions on the microstructure, texture and mechanical properties of Ti6Al4V alloy

Abstract

The evolution of microstructure and texture of Ti6Al4V alloy developed by cold rolled followed by annealed treatment at a thickness reduction ratio of 15%–70% were investigated by scanning electron microscopy and x-ray bulk texture measurement technique. It was found that the grains were severely broken up and elongated by cold rolling, and the degree of the mechanical anisotropy of the Ti6Al4V alloy was increased. For the cold-rolled Ti6Al4V alloy, recovery and recrystallization occurred during annealed treatment under 840 °C for 40 min. The thickness reduction ratio of 10% and 30% of the cold-rolled sheets only partially recrystallized.occurred partial recrystallization. When the thickness reduction ratio reaches 50%, the deformation band structure disappears. Compared to the cold rolled Ti6Al4V alloy, the mechanical anisotropy of the annealed Ti6Al4V alloy was weaker, mainly related to the texture components. The (0001) and components dominate the texture of the cold rolled Ti6Al4V alloy. Among them, and texture components inherit the original microstructure, and the intensity of that was increased with thickness reduction ratio increased. However, the intensity and volume fraction of the texture components rapidly increased and the intensity of the texture and (0001) components were weakened by the annealed treatment. During the annealing treatment, the texture component orientation is gradually strengthened by consuming other scatted orientations. In addition, it can be found that an increase in the intensity and volume fraction of texture component has a positive effect on improving the mechanical anisotropy of the Ti6Al4V alloy.