Crack fault of rotor blades occurred during performance experiment of an axial flow compressor. According to the structure characteristics of the compressor

the time-domain signal

frequency-domain signal of vibration response and high-frequency fluctuation were analyzed

and vibration characteristics of blisk with cracking blades on axial flow compressor were summarized. The results show that the blisk with cracking blades can cause vibration response of the axial flow compressor to present the nonlinear characteristics and the splitting of formant in the vibration frequency range

indicating the blade crack could induce mistuning of the first-stage rotor blisk of the axial flow compressor. With the rise of the speed

the frequencies of two formants fluctuate (periods of fluctuation about 8s and 9.2s respectively)

and the blade crack grows and the number of cracking blades increases

so the mistuning extent of the blisk increases and modal localization of low order modes of the blisk appeares.