Influence of pre-strain and heat treatment on subsequent deformation behavior of extruded AZ31 Mg alloy

预应变和热处理对AZ31镁合金形变行为的影响（英文）

Pre-compression and heat treatment were performed on an extruded AZ31 Mg alloy,and their effects on subsequent deformation behavior were investigated.The results show that at low temperature annealing(170 ℃ for 4 h),the extruded samples with and without annealing exhibit a nearly equivalent yield stress(~148 MPa) because their microstructures are nearly unchanged.However,under the same annealing condition,the yield stress of sample with pre-twinning and subsequent annealing(~225 MPa) is higher than that of the pre-twinned one(~200 MPa).The former sample presents a hardening effect because the solute atoms segregated on twin boundaries lead to a strengthening effect.The pre-twinned sample annealed at 400 ℃ for 1 h shows a higher ultimate elongation(~28%) than the pre-twinned one(~15%),but its yield stress(~125 MPa) is much lower than that of the pre-twinned one(~200 MPa).

对挤压态AZ31镁合金进行预压缩和热处理,研究预压缩和热处理对其形变行为的影响。结果表明:在低温下退火(170℃退火4 h),试样经过退火处理或未经退火处理的几乎具有相等的屈服强度(~148 MPa),这是由于它们的显微组织几乎没有变化。然而在相同退火条件下,经预压缩并退火的试样的屈服强度(~225 MPa)高于只有预压缩试样的屈服强度(~200 MPa)。由于溶质原子在孪晶界偏析引起强化,前者显示出退火硬化效应。预压缩试样在400℃退火1h后,其伸长率(~28%)高于预压缩试样的伸长率(~15%),但其屈服强度(~125 MPa)低于预压缩试样的屈服强度(~200 MPa)。