喷射沉积5A06铝合金热压缩变形的流变应力行为

Flow stress behaviors of spray-deposited 5A06 aluminum alloy under hot compression deformation

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^-1s^-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。

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.