Ti–6Al–4V alloy with an ultrafine-grained microstructure exhibiting low-temperature–high-strain-rate superplasticity

Superplasticity in microcrystalline Ti–6Al–4V (mass%) alloys is exhibited under high temperatures more than 1123 K and low strain rates less than 10−3 s−1, thereby restricting their practical application to specialized areas such as aerospace. We herein identify a new type of Ti–6Al–4V alloy exhibiting low-temperature (below 973 K)–high-strain-rate (10−2 s−1) superplasticity. The ultrafine-grained Ti–6Al–4V alloy was produced by simple hot orking of an α′-martensite microstructure alloy, and it has a great potential for application as cost-affordable superplastic Ti alloy.

Graphical AbstractTi-6Al-4V alloy with an ultrafine-grained microstructure exhibiting low-temperature-high-strain-rate superplasticity.The new type of UFG microstructure Ti-64 alloy employed in this work can be easily produced by a conventional hot-working process by deforming an α′-martensite microstructure under an optimized set of conditions to facilitate sufficient DDRX. Thus produced α′-UFG alloy enables low-temperature (below 973 K)—high-strain-rate (10−2 s−1) superplastic behavior.Figure optionsDownload full-size imageDownload as PowerPoint slide