IN706高温合金的高温压缩变形力学行为及本构方程

Mechanical Behavior and Constitutive Equation of High Temperature Compression Deformation of IN706 Super-alloy

摘要:

IN706高温合金对热加工工艺参数特别敏感，在1143~1393 K、应变速率为0.01、0.1、0.5和1 s^-1的等温压缩条件下将IN706高温合金分别压缩30%、45%和60%，研究了IN706高温合金的流变应力。采用指数型Zener-Hollomon方程来描述应变和温度对热变形的影响，同时在考虑应变补偿的本构方程中考虑了α、n、Q和lnA等不同材料常数的应变效应，并对相关系数R和平均绝对相对误差进行了验证。在构建本构方程的基础上，绘制了IN706高温合金的热加工图，并根据Murty准则给出了不稳定区域。结果表明，应变速率0.1 s^-1、温度1313~1353 K是合理的热加工工艺参数窗口。

Abstract:

IN706 superalloy is particularly sensitive to the parameters of hot working process. The flow stress of the IN706 superalloy was investigated during reduction deformation of 30%, 45%, and 60% under the isothermal compression conditions of temperature at 1143–1393 K and strain rate at 0.01, 0.1, 0.5, and 1 s^-1. The exponent-type Zener-Hollomon equation was used to describe the impact of strain and temperature on the thermal deformation. Meanwhile, the strain effect of various material constants, such as α, n, Q, and lnA, was considered in the constitutive equation considering the strain compensation, and the correlation coefficient R and the average absolute relative error were verified. On the basis of constitutive equation construction, the hot processing map of IN706 superalloy was drawn, and the instability region was obtained based on the Murty criterion. Results show that the reasonable thermal working process parameter window is strain rate of 0.1 s^-1 and temperature of 1313–1353 K.