Synergy in hybrid multi-scale particles for the improved formability of Al–Zn–Mg–Cu alloys

The synergy in hybrid multi-scale particles formed by a novel thermomechanical processing for the improved formability of Al–Zn–Mg–Cu alloys was systematically investigated. The results show that the multi-scale particles can give a positive effect on the fine-grained microstructure, weakened texture and improved formability of the alloys in the pre-aging condition. The effect of multi-scale particles is related to the type and distribution of the hybrid particles, the interactions between the particles, the concentrations and the processing method. The existence of synergy between different types of iron-rich phases, as well as precipitates, shows great potential and could significantly increase applications of high strength Al–Zn–Mg–Cu alloys with high formability.