Nb10Zr合金高温变形应变补偿型本构关系模型

High-Temperature Deformation Constitutive Relationship Model Considering Strain Compensation of Nb10Zr Alloy

摘要:

针对一种新型的铌基高温功能合金Nb10Zr，在变形温度1273~1373 K和应变速率0.01~1 s-1条件下，利用Gleeble-1500型热模拟试验机进行等温恒应变速率压缩试验，对其高温变形行为进行研究，并建立了应变补偿的材料高温变形Arrhenius本构关系模型。确定了峰值应力、变形温度和应变速率之间的关系，并考虑了应变的影响，获得了变形激活能和本构方程中材料常数随应变的变化规律。结果表明，在较低温度下所建立的本构关系模型可以精确预测材料的变形行为，但随着变形温度的升高，本构模型的预测能力有所下降，但在所研究的变形温度和应变速率范围内应变补偿型本构关系模型能够满足工程需要，平均相对误差为4.3%

Abstract:

High-temperature deformation behavior of a new type of Niobium-based superalloy Nb10Zr was investigated by the Gleeble-1500 thermo-mechanical simulator compression test at deformation temperatures of 1273~1373 K and strain rates of 0.01~1 s-1. The Arrhenius constitutive equation with the strain compensation was established based on the experiment data. The relationship between peak stress, strain rate and deformation temperature was also established. Furthermore, the law of activation energy and material constants with the variation of true strain is obtained in consideration of the strain influence. The results show that the constitutive model could accurately predict the deformation behavior at low temperature, but the bad predicting ability occurs with increasing deformation temperature. However, the new improved constitutive model could meet the engineering need in the range of strain rate and deformation temperature in this study and the average relative error of 4.3% is relatively low