Microstructure and Texture Development of Pure Aluminum and Aluminum Alloy Processed by High Speed Hot Rolling

The microstructure and texture development of pure aluminum and aluminum alloy processed by high speed hot rolling are investigated. The aluminum sheets are rolled at temperatures ranging from 410 oC to 560 oC at a rolling speed of 15 m/s without lubrication and quenched into water at an interval of 30 ms after rolling. The redundant shear strain induced by high friction increases beneath the surface at a reduction above 50% for Al alloy (AA5052) and above 60 % for pure Al (AA1050). Dynamic recrystallization occurs in the surface region when the equivalent strain exceeds a critical value that depends on rolling temperature, while only recovery occurs in the center region. The critical equivalent strain for the occurrence of recrystallization in AA5052 is lower than that in AA1050. When the large shear strain is introduced beneath the surface, the shear texture, the main components of which are {001}<110> and {111}<110>, develops. In the center region, Cu-orientation and cube orientation develop. The shear texture beneath the surface is weak when recrystallization occurs.