B22-O-08Influence of heating rate on microstructure and recrystallization behavior of Al-Zn-Mg-Cu alloy after rolling

Abstract

The influence of heating rate on recrystallization behavior and texture of Al-Zn-Mg-Cu alloy are investigated using a Gleeble thermo-mechanical simulator and air furnace. Al-Zn-Mg-Cu aluminum alloy is rolled to 70% reduction and subsequently annealed at heating rates from 1 to 600 °C /min to the peak temperatures in the range 350 to 500 °C. The results show that recrystallization and texture are depended on the heating rate and the peak temperature. In the case of low heating rate, recovery accompanied by particle dissolving leads to a decrease in the driving force for recrystallization during early stage recrystallization. Enough time allow nucleus to grow and form the coarse elongated recrystallized grains. The recrystallization texture consist of a relatively strong {014} <100> and {114} <110> textures. As the heating rate increased, due to the absence of low temperature recovery, most stored energy is retained to the high temperatures (≥ 450 °C ) and promote recrystallization, leading to fine grain size and high recrystallization fraction. The recrystallization texture is characterized by random texture and the remainder rolling texture.