Failure analysis of J85-CAN-15 turbojet engine compressor disc

This paper analyzes the J85-CAN-15 engine damage due to fracture of the compressor disc 8th stage dovetail post. An Inner Object Damage (IOD) phenomenon was identified. The damaged compressor disc material is Incoloy 901 forging. The composition of the disc is determined as 42.7%-Ni, 34%-Fe, 13.5%-Cr, 6.2% Mo, 2.5%Ti, 0.1%-Cu, and 0.05%-C. The average hardness value of the material is 44 HRC. The burrs have been observed under Field Emission Scanning Electron Microscope (SEM) and they are considered as the origin of the fatigue on the engine compressor disc. The metallurgical analysis results show that manufacturing defect was propagated under the repeated low and high cyclic loads.