Preferential dynamic recrystallization at original grain boundaries in the hot-rolling process of AZ31 alloy

Abstract

Single pass hot-rolling was conducted on commercial AZ31 magnesium alloy. Dynamic recrystallization (DRX) preferentially initiated at original grain boundaries in the hot-rolling process, producing the characteristic necklace-like microstructure at higher strain stage. Electron back-scattering diffraction (EBSD) was used to investigate this preferential DRX at grain boundaries. Progressive orientation gradient was found to be involved in subgrain formation, while DRX did not follow previous orientation gradient from matrix and had a tendency to align their (0 0 0 2) plane with shearing plane as they got close to the middle layer of DRX region, which was ascribed to the expanding effect of localized shearing strain. Show more