在Gleeble-1500D热模拟试验机上,采用高温等温压缩试验对Cu—Ni-Si—P—cr合金在应变速率为0.ol~5S-1、变形温度为600~800℃条件下的流变应力行为进行研究,利用光学显微镜分析合金在热压缩过程中的组织演变及动态再结晶机制。结果表明:Cu—Ni—Si-P—Cr合金在热变形过程中发生了动态再结晶,且根据变形温度的不同,真应力-真应变曲线的特征有所不同。流变应力随变形温度升高而降低,随应变速率提高而增大。从流变应力、应变速率和温度的相关性得出该合金热压缩变形时的热变形激活能Q和本构方程。
The flow stress behavior of Cu-Ni-Si-P-Cr alloy during hot compression deformation was studied by isothermal compression test at Gleeble-1500D thermal-mechanical simulator under condition of the temperature from 600 ℃ to 800 ℃ and the strain rate from 0.01s-1 to 5 s-1. The microstructure evolution and dynamic recrystallization nucleation mechanisms of Cu-Ni-Si-P-Cr alloy were analyzed. The results show that the dynamic recrystallization occurs during hot compression deformation. The characteristics of the true stress--true strain curve are different when the deformation temperature is different. The flow stress decreases with the increase of deforming temperature, while increases with the increase of strain rate. Both the hot deformation activation energy Q and constitutive equation are derived from the correlativity of flow stress, strain rate and temperature.