AZ80镁合金高温塑性研究

Plastic Deformation of AZ91 Magnesium Alloy at Elevated Temperature

对变形镁合金AZ80高温流动行为进行了研究,确定了AZ80高温变形时的最佳工艺参数,建立了AZ80的流动应力模型,找出了影响变形参数的因素。结果表明,AZ80有应力峰和变形软化特征,在ε≥0.3时,流动应力趋于稳定状态。在热加工图中应变速率为10s-1、变形温度为370℃附近区域对应的工艺参数最佳。在中温(300～370℃)时,组织以动态再结晶的等轴晶为主,晶粒均匀细小,表现出良好的综合性能。

The flow stress model of AZ80 magnesium alloy has been established to determine the optimal processing parameters of AZ80 magnesium at elevated temperature and to obtain the factors influencing deformation variables by observing the rheological behavior of the alloy.The results reveal that there exists stress peak and deformed softening characteristics in AZ80 magnesium,in which the flow stress would keep a stable value with the strain more than 0.3.The optimal processing parameters can be obtained with strain rate of 10 s-1 at 370 ℃ in the processing map.The uniform and fine dynamic recrystallized equaixed grain is dominant in the microstructure of the AZ80 wrought alloy,exhibiting excellent mechanical properties.