Deformation characteristics of Ti-6Al-4Fe alloys with enhanced high temperature ductility

Deformation behavior of Ti-6Al-4Fe alloys with high strength and formability was investigated by conducting high temperature tensile test. In tensile test at room temperature, the strength of Ti-6Al-4Fe alloys was higher than that of a commercial Ti-6Al-4V alloy with a similar level of elongation. In particular, the high temperature (700 °C) elongation was dramatically increased in Ti-6Al-4Fe alloys showing ∼800% superplasticity. Grain boundary sliding and suppression of cavity formation (i.e., easier accommodation) during gb sliding due to beta phase were found to be possible mechanisms for the superplasticity of Ti-6Al-4Fe alloys.