The in-service fatigue fracture mechanisms for the I-stage low-pressure compressor disk of the aircraft engine D30KU-154

This paper contains the in-service fatigue fracture analysis for the first stage low-pressure compressor disk of the aircraft engines D30KU-154. Based on the results of the fractographic investigation on collapsed compressor disks the fatigue crack initiation and propagation principles were established. It is shown that the crack initiation in the rim part of the compressor disk is due to a high frequency loading that leads to very high cycle fatigue fracture. The total fatigue lifetime of the compressor disk is determined by simultaneous action of low amplitude loading due to blades vibration, and high amplitude loading due to flight cycle (centrifugal forces). Study of in-service fracture of the compressor disk was based on the evaluation of numerical simulations of the stress state in the damaged zone under corresponding loading conditions. The estimation of fatigue lifetime and crack path predictions were performed based on the multiregime fatigue fracture model developed by the authors.