Superplastic behaviour in nominally single-phase and two-phase AI-Cu alloys

Abstract

Elevated temperature tension tests and metallographic studies have been made with nominally single-phase and two-phase AI-Cu alloys containing different volume fractions of CuAl2 phase, in order to gain a better understanding of superplastic deformation mechanism in a two-phase alloy. The superplastic deformation behaviour in these alloys may be explained quantitatively on the assumption that grain boundary sliding is accommodated by slip in α-AI phase and by diffusion in CuAl2 phase, and both phases are deformed at the same rate.