使用Gleeble-3800型热加工模拟实验机,在温度1000-1200℃、应变速率1-80 s^-1、最大变形程度为70%的条件下对IN690高温合金的流动应力进行高温等应变压缩实验。分析了流动应力与工艺参数之间的关系,并基于Arrhenius方程对所得的实验数据进行处理,构建出了该材料的本构关系方程。误差分析结果表明,该本构方程最大相对误差为18.1%,平均相对误差为8.2%,具有较好的精度,可适用于实际应用。同时通过线性回归的方法计算出该材料的应变激活能、应力指数等数值,为IN690高温合金数值模拟提供参考。
Equal strain compression experiment of flow stress on IN690 superalloy at high temperature was conducted by Gleeble -3800 hot simulator with the temperature from 1000 to 1200 ℃, strain rate from 1 to 80 s^- 1 and maximum plastic deformation of 70%. The relationship between flow stress and technological parameters was analyzed. The obtained experimental data was processed based on Arrhenius equation and the constitutive relationship of IN690 superalloy was constructed. The results of error analysis show that the maximum relative error is 18.1% and the average relative error is 8.2% of the constitutive, which presents better precision and can be applied to practice. Meanwhile, the stress exponent and activation energy etc. are also gained by linear regression method, which provide a reference for numerical simulation of forging process of IN690 superalloy.