Microstructural gradients in the superplastic forming of Ti-6Al-4V

Abstract

The effect of microstructural gradients, introduced by local induction heating, on the behavior of a Ti-6Al-4V sheet in superplastic forming has been investigated. Heat treatment led to a change in the morphology of the α phase present at the start of superplastic deformation, which caused an increase in initial flow stress. This has a significant effect on the strain distribution. Trials using two axially symmetric shapes showed that the effect of microstructural gradients can be adequately predicted-via numerical modeling-and controlled. The technique has the potential to control the thickness distribution in formed parts.