Abstract
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.