Mg-Y-MM-Zr合金流变应力模型的建立及应用(英文)

Establishment and application of flow stress models of Mg-Y-MM-Zr alloy

在GLeeble1500D热模拟机上研究Mg-9Y-1MM-0.6Zr(WE91)合金的热变形行为,其变形温度为653773K,变形速率为0.0011s1,变形程度为60%;建立WE91合金流变应力预测模型。结果表明:合金的应力和应变之间的关系受变形温度及变形速率的影响,合金在高温变形过程中的流变应力可以由含Zener-Hollomon参数的双曲正弦函数表征,建立的数学模型可以很好地预测合金的流变应力,说明该模型可以很好地反映WE91合金的变形本质;合金在真应变为0.1时的平均激活能为220kJ/mol;变形温度和变形速率对WE91合金的变形组织也有明显的影响。

The hot working behaviors of Mg-9Y-1MM-0.6Zr （WE91） magnesium alloy were researched in a temperature range of 653 773 K and strain rate range of 0.001 1 s 1 on Gleeble 1500D hot simulator under the maximum deformation degree of 60%. A mathematical model was established to predict the stress—strain curves of this alloy during deformation. The experimental results show that the relationship between stress and strain is obviously affected by the strain rates and deformation temperatures. The flow stress of WE91 magnesium alloy during high temperature deformation can be represented by Zener-Hollomon parameter in the hyperbolic Arrhenius-type equation, and the stress—strain curves obtained by the established model are in good agreement with the experimental results,which prove that the model reflects the real deformation characteristics of the WE91 alloy. The average deformation activation energy is 220 kJ/mol at strain of 0.1. The microstructures of WE91 during deformation processing are influenced by temperature and strain rates.