Study on surface fatigue and metamorphic layer of raceway of hybrid ceramic ball bearing in high-speed spindle for machine tool

•A metamorphic layer forms on the upper surface of the bearing raceway under the cyclic contact stress.•Stress-induced effect plays an important role in the transformation from the common martensite structure to the metamorphic layer.•Under the cyclic contact stress, the dislocation pile-up groups form in carbide particles, and the carbide particles can even be elongated and crushed.•The cracks initiate and propagate near the metamorphic layer, which leads to the peeling band, the surface fatigue damage and premature failure of the precision bearings.