高耐蚀仿金黄铜合金的热变形行为及显微组织演变

Hot deformation behaviour and microstructure evolution of gold-imitation brass alloy with high corrosion resistance

通过热压缩实验研究Cu-13Zn-1Ni-1Sn-1.5Al仿金黄铜在温度为953~1123 K和应变速率为0.001~1 s^(-1)条件下的热变形特征。应力-应变曲线表明,流动应力随着温度的升高和应变速率的降低而降低。在0.01 s^(-1)的恒定应变速率下,当温度达到1073 K时,合金的显微组织中出现动态再结晶晶粒。建立合金在不同应变(ε=0.1, 0.2,0.3, 0.4, 0.5, 0.6, 0.7, 0.8)条件下的本构方程并计算其变形激活能。当应变为0.8时,合金的本构方程为=7.22×10^(9)[sinh(0.0187σ)]^(3.67)exp[-227.17/(RT)],变形激活能为227.17 k J/mol。绘制仿金合金在不同应变条件下的功率耗散图和失稳图,得到合金在热压缩工艺中的最佳热变形温度范围为1010~1040 K,应变速率为1 s^(-1)。

The hot deformation characteristics of Cu−13Zn−1Ni−1Sn−1.5Al gold-imitation brass alloy in a temperature range from 953 to 1123 K and a strain rate range from 0.001 to 1 s^(-1) were investigated by hot compression tests.The stress−strain curves show that the flow stress decreases with the increase of temperature and the decrease of strain rate.The dynamic recrystallization grains appear while the temperature reaches 1073 K at a constant strain rate of 0.01 s^(-1).The constitutive equation of the alloy was established and its deformation activation energies were obtained at different strains(ε=0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8).When the strain is 0.8,the constitutive equation of the alloy is ε=7.22×10^(9)[sinh(0.0187σ)]^(3.67)exp[-227.17/(RT)],and the deformation activation energy is 227.17 kJ/mol.The dissipation power maps and instability maps were established at different strains,which suggested that the recommended processing condition for hot compression was in the temperature range of 1010−1040 K with a strain rate of 1 s^(-1).