CARBURIZED BEARING STEEL COMPONENT AND STEEL BAR FOR CARBURIZED BEARING STEEL COMPONENT

摘要

A carburized bearing steel part has a predetermined chemical composition, and, in the carburized bearing steel part, the number density of oxide particles having an equivalent circle diameter of 5 μm or more, and containing CaO, Al₂O₃ and SiO₂, such that the content ratio of Al₂O₃ with respect to the total mass of CaO, Al₂O₃, and SiO₂ is 50% by mass or more, is 3.0/cm² or less in an arbitrary cross section of the part, the Vickers hardness at a depth of 50 μm from a rolling surface is 750 or more, and the compressive residual stress at the rolling surface is 900 MPa or more. Also provided is a steel bar for a carburized bearing steel part that is suitable for obtaining the foregoing carburized bearing steel part.