Superplastic behaviour of nanocrystalline metallic materials

It is theoretically possible to achieve superplasticity at low temperatures and/or high strain rates by reducing the grain size of metallic materials into the nanometer range. This paper describes the fabrication by severe plastic deformation techniques of several model and commercial alloys with nano- and submicrometer grain sizes, the results of their structural characterisation, and provides data on their tensile behaviour. The phenomenon and origin of enhanced superplastic properties observed in the resulting alloys are considered and discussed.