Effect of hot rolling temperature on microstructure formation during annealing of hot-rolled Al-1%Mn alloy

This study investigated the effect of hot rolling temperature on microstructure formation during annealing of a hotrolled Al-1%Mn alloy. After casting, samples were hot rolled at 300°C, 400°C, and 500°C with a reduction ratio of 80%, and then annealed at 300°C, 400°C, and 500°C for various times. Vickers hardness test and electrical conductivity measurements were performed on each annealed sample. Some samples were subjected to FE-SEM/BSE and FE-SEM/EBSD to obtain information on precipitates and crystal orientation. The results obtained suggest that recovery mainly occurred in all the hot-rolled samples when annealed at 300°C, and that recrystallization was completed when annealed at 500°C. At 400°C, the microstructure formation behavior changed depending on the hot rolling temperature, and the change in electrical conductivity suggested that precipitation and recrystallization competed with each other.