Investigations on fretting fatigue in aircraft engine compressor blade

An investigation of several cracked blade tangs in the military aircraft engine compre was conducted to identify the root cause of the failure. These cracks were found during scheduled maintenance with fluorescent penetration inspection. The engine compre blade made of Ti-6Al-4V is attached to compressor rotor by means of inserting retai pin through rotor and blade tang. By analyzing the fracture surface of the failed blade t it is found that the crack in the blade tang was initiated by fretting fatigue and propag under low cycle fatigue. Stress analysis of the blade using a non-linear finite eler method is coincident with the results of fractography. The clearance between retai pin and tang hole caused small amplitude of sliding motion leading to fretting wear du engine operation. Consequently, the damaged area due to fretting wear acts as a stress ser inside tang hole and contributes to accelerate fretting fatigue. (C) 2011 Elsevier Ltd. All rights reser