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.