高锆含量Cu-1%Zr-0.15%Ce合金热变形行为研究

Hot Deformation Behavior of Cu-1%Zr-0.15%Ce Alloy with High Zirconium Content

利用Gleeble-1500D热模拟机,在温度为550,650,750,850,900℃,应变速率为0.001,0.01,0.1,1,10 s^(-1)的条件下,对Cu-1%Zr-0.15%Ce合金的高温变形过程中的流变应力进行研究,分析了动态再结晶的演变机制。结果表明:变形温度和应变速率对合金的流变应力有显著的影响,在550~750℃之间具有典型的动态回复特征,850~900℃具有动态再结晶热变形特征。通过流变应力、应变速率和变形温度之间的关系,建立高温热变形流变应力本构方程,得到合金的热激活能为430.51 k J·mol^(-1),与纯铜热压缩变形过程相比,高Zr含量Cu-1%Zr-0.15%Ce合金热激活能提高了105%。

The flow stress curves of Cu-1. 0% Zr-0. 15% Ce alloy during high temperature deformation were studied by using a Gleeble-1500 D thermal simulation machine at the hot deformation temperature of 550,650,750,850 and 900 ℃,the strain rates of 0. 001,0. 01,0. 1,1 and 10 s（-1）,respectively. The evolution mechanism of dynamic recrystallization was analyzed. The results showed that the deformation temperature and strain rates had significant influence on the flow stress of the alloy. The typical characteristics of dynamic recovery occurred during the deformation temperature of 550 - 750 ℃,while the characteristics of dynamic recrystallization occurred during the deformation temperature of 850 - 900 ℃. Through the relationship among the flow stress,strain rates and deformation temperature,and the hot deformation flow stress constitutive equation was established. The hot deformation activation energy was 430. 51 k J·mol（-1）. Compared with hot compressive deformation process of pure copper,the hot deformation activation energy of Cu-1% Zr-0. 15% Ce alloy with high Zr content increased by 105%.