Failure Analysis on Cracking of Train Wheelset Bearing Outer Ring

Cracking occurred to a train wheelset bearing outer ring after running for about 6×105 km, and the cracking reasons were analyzed by means of chemical compositions analysis, metallographic examination, hardness test and fracture analysis. The results show that corrosion pits formed on surface of the bearing outer ring in corrosive medium environment, which induced notch effect and stress concentration. So micro cracks initiated from the corrosion pits and continuously propagated under action of the mechanical stress and residual stress, which finally resulted in cracking of the bearing outer ring.