(湖南大学 材料科学与工程学院, 长沙 410082)
摘 要: 采用Gleeble-1500热模拟机对喷射沉积5A06铝合金进行等温热压缩实验, 变形温度为300~500 ℃, 应变速率为5×10-4~5×10-1 s-1, 最大变形程度为50%。 结果表明: 喷射沉积5A06铝合金热压缩变形流变应力受变形温度和应变速率的强烈影响, 可以用Zener-Hollomon参数的双曲正弦函数形式进行描述。 在本研究条件下, 喷射沉积5A06铝合金热压缩变形时的热变形激活能Q及应力指数n均随着应变的增加而减小。 根据Zener-Hollomon本构方程得出的流变应力拟合值与实测值吻合较好。
关键字: 喷射沉积; 5A06铝合金; 热压缩变形; 流变应力; 本构方程
(College of Materials Science and Engineering, Hunan University,
Changsha 410082, China)
Abstract: The hot compression tests of spray-deposited 5A06 aluminum alloy were performed on Gleeble-1500 machine at temperatures of 300-500 ℃ with constant strain rates of 5×10-4-5×10-1 s-1. The results show that the flow stress behaviors strongly depend on the deformation temperatures and strain rates, which can be represented by Zener-Hollomon parameter in the hyperbolic-sine-type equation. Both the hot deformation activation energy Q and the stress index n derived from the experiments decreases with the strain rate increasing. The predicted stresses agree well with experimental results.
Key words: spray deposition; 5A06 aluminum alloy; hot compression deformation; flow stress; constitutive equation