Al-Er-Zr合金的热变形行为及动态析出

Hot deformation behavior and dynamic precipitation in Al-Er-Zr alloy

摘要:

通过对Al-0.04Er-0.08Zr合金进行200°C 到450°C 范围内的热压缩测试对该合金的热变形行为进行了研究，在这个过程中利用Arrhenius-type方程进行线性拟合从而分析应力-应变曲线，之后通过透射电镜来观察研究变形组织。结果表明对于固溶态以及时效态合金来讲，在热压缩过程中动态回复是使合金软化的一个主要机制。高温以及低应变速率的热变形会诱导固溶态合金快速析出。动态析出会明显增加固溶态合金在热压缩过程中其表面的流变应力，但是却不能有效提高变形合金的硬度。动态析出还会导致应力-应变曲线拟合出现Arrhenius型偏差。

Abstract:

The hot deformation behavior of Al-0.04Er-0.08Zr alloy was investigated by hot compression tests in the temperature range from 200°C to 450°C. True stress-true strain curves were analyzed by linear fitting using Arrhenius-type equation, and deformation microstructure was studied by TEM. The results indicate that dynamic recovery is the dominated softening mechanism for both the solutionized and the aged sample during hot compression. Hot deformation especially at high temperature and low strain rate induced rapid precipitation in the solutionized samples. Dynamic precipitation apparently led to the increase of the flow stress of the solutionized samples during hot compression process, but did not effectively enhance the microhardness of the deformed samples. The dynamic precipitation also led to deviations of the Arrhenius-type fitting of the stress-strain curves.