基于非线性振动的联轴器膜盘振动疲劳试验研究

Experimental Study of Vibration Fatigue of Coupling Diaphragm Based on Nonlinear Vibration

介绍了航空发动机联轴器TC4钛合金膜盘振动疲劳的试验研究。通过建立闭环控制下的振动疲劳试验系统,得到了该膜盘在不同激励条件下的频率-位移响应曲线,由此阐明了联轴器膜盘在大挠度条件下的非线性振动特性。基于该特性进一步开展膜盘在非线性振动条件下的振动疲劳试验研究,给出了该膜盘的径向应力-疲劳寿命曲线以及疲劳极限值。最后分析了膜盘振动疲劳的主要破坏形式。结果表明,膜盘疲劳极限值介于其母体材料的中值疲劳极限值和高可靠度疲劳极限值之间,而主要破坏形式包括可见表面裂纹和表面剥落。

This paper presents a vibration fatigue experimental study of TC4 titanium alloy coupling diaphragm used in aeronautical engine. Through establishing a closed-loop controlled vibration fatigue experimental system, the frequency-displacement response curve of diaphragm was obtained under different excitation conditions. Thus, the nonlinear vibration characteristics of coupling diaphragm under large deflection condition were clarified. Based on the above result, experimental study of diaphragm vibration fatigue under nonlinear vibration condition was carried out further. The radial stress-fatigue cyclic life curve and fatigue limit strength of diaphragm were obtained. Finally, the main failure mode of coupling diaphragms was analyzed. Results show that the fatigue limit strength of coupling diaphragms is between the median fatigue limit strength and high reliable fatigue limit strength of corresponding matrix material. The main fatigue failure modes include visible surface cracks and spalling.