Influence of Rolling Temperature on Microstructure and Tensile Properties of AZ31 Sheets

Abstract

Microstructure and tensile properties of AZ31 rolled at different temperatures were characterized. Rolling of extruded AZ31 plates was carried out at room temperature, 573K, 623K and 673K. Cold rolling of extruded AZ31 plates was difficult due to the poor formability at room temperature. And deformation twinning plays an important role in rolling of AZ31 alloy at room temperature. The microstructural analysis showed that the nucleation of dynamic recrystallization (DRX) occurred at 573K, DRX was almost completed at 623K and grain growth was determined at 673K. The ultimate tensile strength (UTS) as large as 377MPa was achieved after rolled at 573K. And the anisotropy in strength was obviously examined due to the rolling texture. The anisotropy reduced as rolling temperature increasing from 573K to 673K and this may be attributed to the completion of DRX.