ZK60镁合金热变形过程中的应变强化与动态再结晶行为

摘要

研究ZK60合金的高温流变应力行为.分别采用Kocks-Mecking模型和Avrami方程对合金的应变强化和动态再结晶过程进行模拟,在此基础上,构建一个考虑合金动态再结晶软化的流变应力方程并对流变应力进行预测.结果表明:预测曲线与实验结果具有很高的相关系数,所构建的流变应力方程能准确地描述热变形过程中合金的流变应力行为.微观组织观察表明在变形初期合金组织主要为动态回复组织,随着应变增加,逐渐转变为再结晶组织.%The flow stress behavior of ZK60 alloy at elevated temperature was investigated.The strain hardening and dynamic recrystallization of the alloy were modeled by Kocks-Meching model and Avrami equation,respectively.A new constitutive equation during hot deformation was constructed to predict the flow stress considering the dynamic recrystallization.The results show that the flow stress curves predicted by the proposed equation have high correlation coefficients with the experimental data,which confirms that the developed model is accurate and effective to establish the flow stress equation of ZK60 magnesium alloy during hot deformation.Microstructure observation shows that dynamic recovery occurs in the initial stage of hot deformation.However,the microstructure turns to recrystallization structure as the strain increases.