Superplastic deformation of an as-rolled Al–Cu–Mg–Ag alloy

An as-rolled Al–Cu–Mg–Ag alloy was found to show good superplastic properties at temperatures higher than 450 °C and strain rates slower than 10−2 s−1. A maximum elongation-to-failure of 320% was observed at 500 °C and 5 × 10−4 s−1. The strain rate sensitivity exponent is as high as 0.58. The dominant deformation mechanism in high strain rates is grain boundary sliding, accompanied by atom diffusion and dislocation multiplication.