GH4169合金不同热变形条件下的流变应力研究

在Gleeble－3500型热加工模拟试验机上进行了GH4169镍基合金的高温压缩试验，变形温度为980℃～1100℃、应变速率为0，01s^-1、0，1s^-1、1s^-1、10s^-1，变形程度为50％。通过绘制真应力一真应变曲线，研究了GH4169镍基高温合金高温下的流变应力行为。结果表明：GH4169是应变速率和变形温度敏感型材料，变形温度升高和应变速率减小使流变应力显著减小；在变形的初始阶段，流变应力迅速增加，在到达峰值后，随着应变的增加，流变应力逐渐下降，并趋于一稳定值。采用简化后的双曲正弦模型Arrhenius方程，建立了GH4169高温条件下的本构方程，运用该方程计算出的峰值应力与试验测量值相比，拟合度达到了95.95％。

Flow Stress of GH4169 Alloy Under Different Hot Deformation Conditions

The high temperature compression tests of GH4169 is carried out on the Gleeble-3500 thermal-mechanical simulator, in the temperature ranging from 980℃ ～ 1100℃ and strain rate ranging from 0.01 to 10 s^-1 ,and the deformation degree of 50%. The flow stress of GH4169 nickel-based superalloy in high temperature is studied by the true stress and true strain curve. It is concluded that GH4169 superalloy is sensitive to strain rate and the temperature. The flow stress declines with the increase of temperature and the decrease of the strain rate. In the initial stage of deformation,the flow stress increases rapidly, up to the peak, the flow stress de- creases gradually with the increase of the strain, and tends to a stable value. Constitutive equations of GH4169 superalioy in high temperature are obtained, based on simplified hyperbolic sine model Arrhenius equation. Comparing peak stresses calculated by the equation, to the measured values, the similarity is up to 95.95%.