An experimental and theoretical study of surface rolling contact fatigue damage progression in hybrid bearings with artificial dents

An experimental study followed by modeling is carried out for pre-dented hybrid rolling bearings to observe the raceway surface damage evolution and to try to understand its behavior. The experiments and modeling are repeated in similar all-steel bearings and conditions for comparison purposes. The results show that hybrid bearings tend to re-accommodate the dent raised edges on the steel surface by mild wear and plastic deformation and this stabilizes the local pressures much faster than all-steel bearings. Followed by a lower boundary friction coefficient, when the lubricated oil is broken by the surface features, hybrid bearings give still longer dent lives than the all-steel bearings, even though the conditions are at equal bearing load (which means higher stresses in the hybrid bearings).