Influence of heat treatment on the microstructural evolution of Al–3 wt.% Cu during high-pressure torsion

Abstract

Solution-treated, peak-aged and overaged samples of the model alloy Al–3 wt.% Cu, obtained by selective heat treatments of the pre-material, have been subjected to high-pressure torsion at room temperature and at 200 °C. The mechanical behaviour of the samples was investigated with torque measurements during deformation and microhardness measurements after deformation. Irrespective of the initial material condition, in the saturation regime a comparable equilibrium microstructure was found consisting of ultrafine aluminium grains stabilized by precipitates formed at grain boundaries.