GH4169高温合金疲劳寿命非线性超声检测研究  

GH4169 Superalloy Fatigue Life Detection Using Nonlinear Ultrasonic

作　　者：阎红娟 刘峰斌[1] 潘勤学 YAN Hong-juan;LIU Feng-bin;PAN Qin-xue(College of Mechanical and Materials Engineering, North China University of Technology, Beijing 100144, China;School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China)

机构地区：[1]北方工业大学机械与材料工程学院,北京100144 [2]北京理工大学机械与车辆学院,北京100081

出　　处：《机械设计与制造》2019年第2期127-130,共4页Machinery Design & Manufacture

基　　金：国家自然科学基金资助项目(51305028);国家自然科学基金资助项目(50575004);北京市自然科学基金资助项目(3162010);北方工业大学科研启动基金项目

摘　　要：基于超声无损检测理论,研究金属板材弯曲疲劳引起的超声非线性波动规律,建立相对非线性超声系数β′、δ′与基波、谐波幅值定量关系。利用位错模型解释了金属材料存在晶格微缺陷或应力时,超声二阶与三阶非线性系数β、δ的变化趋势。建立非线性超声检测系统,测量GH4169高温合金板材疲劳弯曲试验过程中超声相对非线性系数β′、δ′的变化趋势。实验结果表明:随着疲劳寿命的增加,相对非线性系数单调增加。二阶与三阶相对非线性系数与疲劳寿命关系转折点分别出现在疲劳寿命80%左右和60%左右。在第一阶段相对非线性系数随着疲劳寿命单调增大,在第二阶段相对非线性系数随着疲劳寿命增加出现波动或保持不变,甚至出现下降现象。对于二阶相对非线性系数,实验曲线与位错综合模型预测数据具有较好的一致性。对于三阶相对非线性系数,实验曲线与位错偶模型预测数据具有较好的一致性。Based on theory of ultrasonic nondestructive testing of fatigue damage in metal components, the wave rules of ultrasonic nonlinearity by fatigue are studied. The relationships of relative nonlinear coefficients β′、δ′ versus fundamental and harmonic amplitudes are determined. The dislocation models are used to expound that micro defects in metal materials cause the changes of the second and third order nonlinear coefficients. The nonlinear ultrasonic testing system is used to detect the changes of the second and third order relative nonlinear coefficients with the fatigue life of GH4169 superalloy. The results shows the relative nonlinear coefficients increase with the fatigue life. There are turning points in curves. In first stage, the relative nonlinear coefficients monotonically increase with the fatigue life. In second stage, the relative nonlinear coefficients change slowly or barely with the fatigue life. For the second order relative nonlinear coefficient, the experimental data is approximately coincident with the data predicted by the dislocation comprehensive models. For the third order relative nonlinear coefficient, the experimental data is approximately coincident with the data predicted by the dislocation dipole models.

关 键 词：非线性超声 位错综合模型 位错偶模型 相对非线性系数 疲劳寿命 

分 类 号：TH16[机械工程—机械制造及自动化] TB553[理学—物理]