在Gleeble.1500D热模拟试验机上,采用高温等温压缩试验,对Cu-2.0Ni-0.5Si-0.4Cr合金在应变速率为0.01~5s^-1、变形温度为600~800℃、最大变形程度为60%条件下的流变应力行为进行了研究。结果表明:随变形温度升高,合金的流变应力下降,随应变速率提高,流变应力增大;在应变温度为700,800℃时,合金热压缩变形流变应力出现了明显的峰值应力,表现为连续动态再结晶特征;从流变应力、应变速率和温度的相关性,得出了该合金高温热压缩变形时的应力指数(n)、应力参数(a)、结构因子(A)、热变形激活能(Q)和流变应力方程;合金动态再结晶的显微组织强烈受到变形温度的影响。
The flow stress behavior of Cu-2.0Ni-0.5Si-0.15Ag alloy during hot compression deformation was studied by isothermal compression test at Gleeble-1500D thermal-mechanical simulator at 600-800 ℃ and at the strain rate from 0.01 to 5 s^-1 under maximum strain of 60%. The results show that the flow stress decreases with the increase of deforming temperature, while increases with the increase of strain rate. When the deformation temperature is 700℃ and 800℃, the flow stress decreases after a peak value, showing continuous dynamic recrystallization. Stress index n, stress scale parameter a, structural factor A, hot deformation activation energy Q, and constitutive equation were derived from the correlativity of flow stress, strain rate and temperature. The microstructure was strongly depended on the deformation temperature.