Cu-2.32Ni-0.57Si-0.05P合金热压缩变形研究

在Gleeble-1500D热模拟试验机上,对Cu-2.32Ni-0.57Si-0.05P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,进行恒温压缩模拟实验研究.分析了实验合金在高温变形时的流变应力、应变速率及变形温度之间的关系,研究了变形温度对合金显微组织的影响.计算了合金高温热压缩变形时的应力指数n、应力参数α、结构因子A以及平均热变形激活能Q.结果表明:合金的流变应力随变形温度升高而降低,随应变速率提高而增大.热变形过程的流变应力可用双曲正弦本构关系来描述.当变形温度高于750℃时,合金流变曲线呈现出明显的动态再结晶特征,合金显微组织为完全的动态再结晶组织.合金的热加工宜在应变速率为0.1～1s-1、温度为700～800℃范围内进行.

Hot compression deformation behavior of Cu-2.32Ni-0.57Si-0.05P alloy

The stress-strain behavior of Cu-2.32Ni-0.57Si-0.05P alloy during hot compression deformation was studied by isothermal compression test on a Gleeble-1500D thermal-mechanical simulator at the strain rate of 0.01 ～ 5 s-1,the temperature of 600 ～ 800 ℃ and the maximum deformation of 60% .The relationship among the flow stress,the strain rate and the deformation temperature was researched.The effect of deformation temperatures on microstructure of the alloy was investigated.The stress index n,the stress scale parameter α, the structural factor A and the main activation energy were determined.Results show that the flow stress decreases with the increase of deforming temperature,while it increases with the increase of strain rate.The flow behavior can be described by the hyperbolic sine constitutive equation.When the deformation temperature is higher than 750℃,the flow curves and microstructures present apparent character istic of dynamic recrystallization.The strain rate of 0.1 ～ 1 s-1 and the temperature of 700 ～ 800 ℃ for hot-working deformation of this alloy are suggested.