Fracture Analysis on Compressor Blade of Aero-engine

The compressor of an aero-engine suddenly broke down during service. After decomposition and checking, the first broken blade was found according to the damage features. Fatigue fracture was confirmed by macro-analysis on the fracture, which originated from the intake side edge. Microscopic analysis on the fracture showed the fatigue fracture was caused by corrosion damage. Analysis on the paint indicated that the corrosion damage was caused by paint breakage around the fracture zone. In the high humidity and salt environment, corrosive ions deposited at the zone of paint breakage. As a result, intergranular corrosion appeared, and then crack initiated and extended until fracture. The paint was broken due to external damage. According to the failure cause, the inspection method of the secondary low-pressure compressor rotor blades in the outfield was refined.