TRACKING OBSERVATION ON SUBSURFACE CRACK IN BEARING STEEL GCr15 UNDER ROLLING CONTACT

Based on the sequent tracking observation on spalling of steel GCr15 under rolling contact fa- tigue,an expression for estimating the propagation of subsurface cracks was derived.The rol- ling contact fatigue life was found to be markedly related to the subsurface crack propagation angle.A new explanation of reason why the rolling contact fatigue life can be prolonged by residual compressive stress and retained austenite was advanced.