The differences in particle structures and recrystallization behaviors between DC and CC AA5052 aluminum alloys

The recrystallization behaviors of direct chill cast (DC) and continuous cast (CC) AA5052 hot bands and cold-rolled hot bands with and without preheating at 454 °C for 4 h were compared. The particle structures of DC and CC AA5052 hot bands and preheated hot bands were investigated. It was found that the differences in recrystallization behaviors between DC and CC AA5052 hot band materials were related to the differences in particle structures between DC and CC AA5052 materials. CC AA5052 hot band contained more Mg2Si particles than DC AA5052. Particle stimulated nucleation (PSN) occurred and resulted in weak recrystallization textures for CC hot band and its cold-rolled hot band. At the same time, DC AA5052 hot band and its cold-rolled hot band recrystallized faster due to the enhanced stored energy of the Mg-rich solid solution. If DC and CC AA5052 hot bands were preheated at 454 °C for 4 h before cold rolling, the Mg2Si particles dissolved, and thus the DC and CC materials had similar particle structures and similar recrystallization behaviors for the cold-rolled preheated DC and CC materials. Therefore, preheating CC AA5052 hot band decreased the structural differences that caused different behaviors in subsequent processing between DC and CC AA5052 materials.