分别用频率修正法、拉伸迟滞能模型、三参数幂函数能量方法和能量法简化模型对三种镍基高温合金材料的热机械疲劳寿命进行预测,并对这些方法的热机械疲劳寿命预测能力进行了评估。结果表明,这些寿命预测方法都能在不同程度上适用于镍基高温合金的热机械疲劳寿命预测,其中能量法简化模型效果最好。热机械疲劳过程中起主导作用的损伤机制与等温疲劳具有一定程度的相似性。从模型寿命预测能力的定量评定可知,只考虑塑性形变的作用时,对反相热机械疲劳寿命的预测效果好于对同相热机械疲劳的预测效果。此外,与其他模型相比,能量法简化模型从能量守恒的角度来看具有一定的理论基础,且预测效果较好,适用于预测镍基合金的热机械疲劳寿命。
Frequency modified method ,Ostergren method ,the energy method of three parameter power function and the simplified energy method were chosen to predict TMF life in three nickel-base superalloys .And the prediction ability of them was assessed .The results indicat that the above methods could predict the TMF life of three nickel-base superalloys at some extent .The simplified energy method among the method was the best .The main damage mechanism of TMF was partly similar to isothermal fatigue .According to quantitative evaluation of life prediction ability to the model ,the effect of fatigue lifetime prediction on out-of-phase was better than in-phase only when the plastic deformation was considered .What's more , the simplified energy method which was based on the law of energy conservation had the rationales . And the prediction capability of that method was better than the other methods .Therefore ,it was suitable to forecast the lifetime of TMF in nickel-based superalloy .