镍基定向凝固高温合金蠕变寿命预测的改进方法  

Improved Method for Creep Life Prediction of Nickel-based Directionally Solidified Superalloys

作　　者：黄佳 贺斟酌 杨晓光[2] 石多奇[2] 孙燕涛 HUANG Jia;HE Zhenzhuo;YANG Xiaoguang;SHI Duoqi;SUN Yantao(School of Aeronautics and Astronautics,Central South University,Changsha 410083;School of Energy and Power Engineering,Beihang University,Beijing 100191;Beijing Aeronautical Engineering Technical Research Center,Beijing 100076)

机构地区：[1]中南大学航空航天学院,长沙410083 [2]北京航空航天大学能源与动力工程学院,北京100191 [3]北京航空工程技术研究中心,北京100076

出　　处：《机械工程学报》2022年第22期258-268,共11页Journal of Mechanical Engineering

基　　金：湖南省自然科学青年基金(2021JJ40741);中南大学中央高校基本科研业务费专项资金(2021zzts0911);国家科技重大专项(2019-IV-0017-0085)资助项目。

摘　　要：一种应用简单、物理依据清晰、稳健的蠕变和持久寿命性能方法是开展航空发动机热端部件强度评价的重要基础。针对航空发动机用典型的镍基高温合金,首先讨论了Wilshire方法对宽温度/应力条件下蠕变性能的预测精度,并证实该方法体系中的等效蠕变激活能比传统方法更接近晶格扩展激活能,所预测的应力分界点与合金不同温度/应力条件下的蠕变变形机制密切相关;其次,通过引入拉伸强度相关的晶向函数对Wilshire和传统的Larson-Miller法进行修正,结果显示修正方法顺利实现了不同晶向下蠕变持久性能的高精度预测;最后,基于Wilshire方法提出了一种基于归一化应力的热强综合参数,该热强综合参数可用于评估高温合金材料在归一化应力条件下的蠕变持久性能,同时基于该热强综合参数有利于发挥材料的高温性能潜能。The important basis for the strength evaluation of aero-engine hot-end components is a simple and robust creep and stress rupture life prediction method with clear physical basis. For aero-engines nickel-based superalloys, the prediction accuracy of Wilshire method for creep properties under wide temperature/stress conditions is firstly discussed, then it is proved that the equivalent creep activation energy in this method system is closer to the lattice expansion activation energy than the traditional method, and the predicted stress cut-off points are closely related to the creep deformation mechanism of the alloy under different temperature/stress conditions. Secondly, the Wilshire method and the traditional Larson-Miller method were modified by introducing the crystal direction function related to tensile strength. The results show that the modified method can successfully predict the downward creep durability of different crystals with high accuracy. Finally, based on the Wilshire method, a thermal strength synthesis parameter based on the normalized stress is proposed. The composite thermal strength parameter can be used to evaluate the creep endurance of superalloy materials under normalized stress conditions. At the same time, based on the composite thermal strength parameter, it is beneficial to exert the potential of the high temperature performance of the material.

关 键 词：Wilshire方法 各向异性 蠕变 镍基高温合金 热强综合参数 

分 类 号：V231[航空宇航科学与技术—航空宇航推进理论与工程]