Effect of heat treatment on microstructure, hardening and plasticity of a commercial Al–Zn–Mg–Cu alloy

This is the authors' abstract. We don't add key points for this paper.

The effect of the heat treatment on the microsturucture and the mechanical response of a commercial Al–Zn–Mg–Cu alloy (AA7075) was studied. The influence of annealing on the hardening and plastic properties of Al–Zn-Mg–Cu alloy was investigated by indentation and tensile tests. The microstructural evolution of the alloy was examined by meant of optical, scanning and transmission electron microscopies. After various ageing states, the Al–Zn–Mg–Cu alloy showed significant changes in microstructure and mechanical behaviour. After quenching, the microstructure was characterized by high ductility. Following ageing at 140 °C, corresponding to the maximum hardness value, the alloy reveals a high volume fraction of small η′ precipitates. The minimum hardening is recorded after ageing at 350 °C. The radical change in the microstructure of the alloy influences its mechanical behaviour, especially in hardening and plasticity.