MoNb合金热变形行为及本构关系

采用Gleeble-3800型热模拟试验机对MoNb合金进行等温恒应变速率压缩试验,研究该合金在变形温度900~1200℃和应变速率0.01~10 s^-1条件下的热变形行为,计算其热变形激活能。结果表明:变形温度和应变速率对流动应力具有显著影响,流动应力随变形温度的升高和应变速率的降低而减小。误差分析表明,采用多元线性回归法建立的MoNb合金本构关系模型具有较高的精度,该模型的预测值误差小于10%的数据点占总数的92.86%,相关系数和平均相对误差分别为0.976和4.08%,能较为准确的预测合金的高温流动应力。

Hot deformation behavior and constitutive relation of MoNb alloy

The constant strain rate compression test of MoNb alloy was carried out by Gleeble-3800 thermal simulator, and the hot deformation behavior of the alloy was studied under deformation temperature of 900-1200 ℃ and strain rate of 0.01-10 s^-1, and the activation energy of the alloy was calculated. The results show that the deformation temperature and strain rate have significant effects on the flow stress of the alloy, and the flow stress decreases with the increase of deformation temperature and the decrease of strain rate. The error analysis shows that the MoNb alloy constitutive relation model established by multiple linear regression method has high accuracy, the data points of the model with error less than 10% account for 92.86% of the total, and the correlation coefficient and the average relative error are 0.976 and 4.08%, respectively, and thus the model can accurately predict the high temperature flow stress of the alloy.