考虑加载频率的超高周疲劳寿命预测  

Ultra-high Cycle Fatigue Life Prediction Considering Loading Frequency

作　　者：舒力力 陈永辉[3] 潘凯 徐乾罡 郭凯 张桢 Lili Shu;Yonghui Chen;Kai Pan;Qiangang Xu;Kai Guo;Zhen Zhang(Department of Engineering Mechanics,School of Aerospace Engineering,Huazhong University of Science and Technology,Wuhan,430074;Hubei Key Laboratory of Engineering Structural Analysis and Sa fety Assessment,Wuhan,430074;National Key Laboratory of Strength and Structural Integrity,Aircraft Strength Research Institute of China,Xi'an,710065;Chinese Aeronautical Establishment,Beijing,100012)

机构地区：[1]华中科技大学航空航天学院,工程力学系,武汉430074 [2]华中科技大学工程结构分析与安全评定湖北省重点实验室,武汉430074 [3]中国飞机强度研究所强度与结构完整性全国重点实验室,西安710065 [4]中国航空研究院,北京100012

出　　处：《固体力学学报》2024年第4期488-495,共8页Chinese Journal of Solid Mechanics

基　　金：国家科技重大专项(J2019-IV-0010-0078);国家自然科学基金项目(12172139)资助。

摘　　要：超高周疲劳试验可以通过传统的电磁振动(30-3000 Hz)、超声振动(20 kHz)等测试方法实现.对于同一材料,采用不同加载频率的测试方法得到的疲劳寿命可能存在差异.为了充分利用不同测试系统得到的超高周疲劳寿命数据,关于考虑加载频率的超高周疲劳寿命预测方法亟待研究.本文结合基于Tanaka的位错理论的裂纹萌生寿命预测模型以及Paris裂纹扩展的寿命预测模型,引入频率对有效应力及疲劳强度的影响,得到超高周疲劳寿命预测模型.利用本文提出的模型,针对钛合金TC17和镍基高温合金GH4169在不同加载频率下的超高周疲劳试验数据进行寿命预测验证,结果显示本文模型能较好地表征不同加载频率下材料的超高周疲劳特性.本文模型建立了不同加载频率下的疲劳寿命数据的关联.Ultra-high cycle fatigue experiments can be conducted using traditional testing methods such as electromagnetic vibration(30-3000 Hz)and ultrasonic vibration(20 kHz).Differences in fatigue life for the same material may arise when tested under varying loading frequencies.To fully utilize the ul-tra-high cycle fatigue life data obtained from different testing systems,the impact of loading frequency on the ultra-high cycle fatigue life of materials needs to be studied imperatively.This paper presents novel prediction models for ultra-high cycle fatigue life,taking into account loading frequency.The models in-corporate the crack initiation life prediction model based on Tanaka's dislocation theory and the Paris crack growth life prediction model.The influence of loading frequency is integrated into effective stress and fa-tigue strength.The proposed models are verified using available very high cycle fatigue test data for titani-um alloy TC17 and nickel-based superalloy GH4169 under different loading frequencies.The results show that the models proposed in this work can reasonably characterize the ultra-high cycle fatigue test data of materials under varying loading frequencies,establishing the correlation of fatigue life data under different loading frequencies.

关 键 词：加载频率 超高周疲劳 寿命预测 

分 类 号：O346.2[理学—固体力学]