Achieving superplasticity in the 7055 aluminum alloy

Abstract

Superplasticity in a 7055 aluminum alloy subjected to intense plastic straining through equal-channel angular extrusion (ECAE) was studied in tension over a range of strain rates from 1.4×10⁻⁵ to 5.6×10⁻¹ s⁻¹ in the temperature interval 300-450°C. The alloy had a grain size of ~1 µm. A maximum elongation-to-failure of ~750% appeared at a temperature of 425°C and an initial strain rate of 5.6×10⁻⁴ s⁻¹, where the strain rate sensitivity coefficient, m, was about 0.46