Characterization of Fatigue Damage of Crankshaft Remanufacturing Core by Two-Dimensional Magnetic Memory Signal

摘要

Fatigue damage degree of crankshaft remanufacturing core was studied based on Metal Magnetic Memory Testing. Bending fatigue test of crankshaft remanufacturing core was conducted on the resonant fatigue test rig and variations of two-dimensional magnetic memory signal distribution in crankshaft pin fillets were studied at different bending fatigue cycle. Experimental research shows that distributions of Hp(x) signals, namely, tangential component of spontaneous stray field and Hp(y) signals, namely, normal component of spontaneous stray field in crankshaft pin fillets have no obvious change with loading cycle when no crack initiation and propagation occur in crankshaft pin fillets. Characteristics of Hp(x) and Hp(y) signal both show dynamic variations when crack in crankshaft pin fillets initiates and extends at medium rate or high rate. Metal Magnetic Memory Testing is a dynamic method for monitoring fatigue crack propagation in crankshaft.