某型钛铝合金航空发动机叶片高温高周振动疲劳实验

以某型钛铝合金航空发动机叶片为研究对象,针对该型叶片高温高周振动疲劳实验时遇到的高温疲劳应力监测、高频激励等问题进行了实验方法研究。采用闭环控制最大应力的方法解决了高温疲劳应力的监测,通过夹具放大设计实现了高频激励,利用辐射加热和电磁振动台完成了温度载荷和振动载荷的综合施加。运用所述的高温高周振动疲劳实验方法,对该型叶片进行了寿命实验。实验的高温疲劳应力控制精度优于±2%,得到该型叶片可靠度为50%的中值疲劳极限是444 MPa,并有效获得了其寿命曲线。该实验方法适合航空发动机叶片高温高周振动疲劳实验,并可为其他航空发动机零部件高温高周疲劳实验提供参考。

Test of vibration fatigue for the TiAl alloy aeroengine blade at high temperature and high cycle

Taking TiAl alloy aeroengine blade as the research object, a series of problems likely to happen during the test of the vibration fatigue for aeroengine blade at high temperature and high cycle were studied, including fatigue stress monitoring at high temperature, and high frequency excitation. The closed loop of maximum stress was used to solve the high-temperature fatigue stress monitoring. The high frequency excitation was realized through design of fixture amplification. The temperature load and vibration load were applied synthetically by radiation heating and electromagnetic vibration shaker. Using the method of the vibration fatigue at high temperature and high cycle, the life test was carried out on the blade. The control accuracy of high temperature fatigue stress was better than ±2%. The median fatigue limit value of the blade with 50% reliability was 444 MPa. The life curve of the blade was obtained effectively. This test method is suitable for the high temperature and high cycle vibration fatigue test of the aeroengine blade, providing a reference to the high temperature and high cycle vibration fatigue test of the other aeroengine parts.