压气机叶片的振动疲劳特性

首次报道了关于采用11CrNi2MoVA材料制造的某型航空发动机压气机第3级叶片振动疲劳特性的研究。结果发现:(1)叶片振动疲劳破坏模式随使用寿命增加而变化。新叶片的破坏位置在叶背最大应力点附近处,而随着使用寿命的增加,叶片破坏位置转向进排气边缘。(2)叶片振动疲劳强度随使用寿命增加而逐渐下降。采用升降法对新叶片、200小时、400小时叶片的实验结果证实了这一点。(3)采用现行方法对叶片的维修有利于叶片疲劳强度的恢复。对使用寿命为400小时的未维修叶片和已完成维修叶片的对比实验表明,维修可使叶片疲劳强度提高,但叶片破坏位置仍在叶片的进排气边缘。 

VIBRATION FATIGUE CHARACTERISTIC OF COMPRESSOR BLADES

Investigation on the vibration fatigue characteristic of the third compressor blades made of steel 1Cr11Ni2W2MoV is presented.A new electro-magnetic eddy-current exciting system has been used to the tests for vibration fatigue strength measuring by up-and-down method.The results show that:(1)The vibration fatigue failure modes of the blades vary with the service duration.The failure location of the new blades is at the maximum stress point on the back of the blade,while with the increasing of the service duration,the failure location changes to the leading & trailing edge of the blades.(2)The vibration fatigue strength decreases with the increase of the service duration that is verified by the up-down method tests on blades in different service durations of 0 h,200 h,and 400 h,respectively.(3)Maintenance of the blades is an effective measure for increasing of the fatigue strength.The comparison tests on the in-maintenance and maintained blades of 400 h service duration show that maintenance of the blades has positive effects on the fatigue strength but the failure location is still at the leading & trailing edge.