Very high strain rate superplasticity in aluminium-based alloys produced from amorphous powders

Abstract

A new aluminium-based crystalline alloy, Al-14wt.%Ni-14wt.%Mm (Mm, misch metal), was prepared by warm consolidation of its amorphous powders. The as-extruded Al-Ni-Mm crystalline alloy had both an ultra fine-grained (70 nm) structure and a uniform distribution of very fine particulates (Al 3Mm and Al 3Ni) of size 70 nm. This alloy, without requiring any subsequent thermomechanical treatment, was found to behave in a superplastic manner at very high strain rates of about 1 s −1 at test temperatures of about 873 K.