Observation of flaking process in rolling contact fatigue of bearing steel with spheroidal inclusions by laminography using ultrabright synchrotron radiation X‐rays

Abstract Rolling contact fatigue tests were performed on specimens containing spheroidal inclusions to clarify the effect of orientation inclusions, and results compared with those stringer‐shaped inclusions. For all types inclusion, cracks first formed rolling surface then propagated in depth direction, an internal crack parallel from deepest point vertical crack, which led flaking. The flaking life was longer than that where initiation propagation lives affected by inclusion shape size. shorter for whereas decreased inclusion. greater scatter size life.