7085铝合金热变形行为特征

Thermal deformation behavior of 7085 aluminum alloy

采用光学金相、热压缩实验和本构方程计算,研究了7085铝合金在不同热变形工艺下的热变形行为。实验结果表明,在热变形温度350~460℃和变形速率0.01~10 s-1范围中,随着7085铝合金变形温度的提高和速率降低,合金的变形峰值应力随之降低,7085铝合金呈现出正应变速率敏感性;采用Arrhenius本构关系构建了7085铝合金热变形的本构模型,并建立了7085铝合金变形温度和速率范围内的热加工图,确定出7085铝合金热变形加工的合适工艺范围温度为420~460℃,应变速率0.01~0.3 s-1。在此工艺条件下,合金变形稳定且易于金属流动。

The thermal deformation behavior of 7085 aluminum alloy at the deformation temperature of 350~460℃and the strain rate of 0.01~10/s-1 was investigated by thermal simulation compression test.The microstructure evolution of the alloy was analyzed by optical microscope(OM).The results show that the flow stress of 7085 Al alloy decreases with the increase of deformation temperature and decrease of strain rate.7085 aluminum alloy is sensitive to positive strain rate.The thermal deformation constitutive model of it was constructed by Arrhenius constitutive relation,and the hot working map in the deformation temperature and rate range was estab⁃lished.The suitable hot deformationtemperature range of 7085 aluminum alloy is 420~460℃,and thesuitable strain rate is 0.01~0.3s-1.