Microstructure and Deformation Behavior of Ti-10V-2Fe-3Al Alloy during Hot Forming Process

Abstract

The microstructure evolution and formability of Ti-10V-2Fe-3Al alloy related to the initial microstructures and processing variables were investigated during hot forming process. The experimental results show that the alpha-phase growth is controlled by solute diffusion during the heat treatment processes. Four different microstructures were established by combinations of several heat treatments, and Ti-10V-2Fe-3Al alloy shows excellent formability both above and below the beta transus temperature. The alloy possesses low deformation resistance and active restoration mechanism during the deformation. A constitutive equation describing the hot deformation behavior of Ti-10V-2Fe-3Al alloy was obtained. Higher flow stress was observed for the acicular morphology of alpha phase in microstructures with large aspect ratios as compared with that of small aspect ratios. Due to the dynamic recovery in soft beta phase, and the dynamic recrystallization and breakage of acicular a-phase, flow softening occurred significantly during deformation. Dynamic recrystallization also occurred especially in the severely deformed regions of forged parts.