ROLLING MEMBER FOR ROLLING BEARING FOR ROLL-NECK IN ROLLING MILL AND ROLLING BEARING FOR ROLL-NECK IN ROLLING MILL

摘要

PROBLEM TO BE SOLVED: To provide a rolling member for rolling bearing for roll-neck in a rolling mill and the rolling bearing for roll-neck in the rolling mill with which rolling fatigue service life under severe circumference, is improved.;SOLUTION: In the rolling member for rolling bearing 15 for roll-neck in the rolling mill, an outer ring 2, an inner ring 3 and a tapered roller 17 are composed of a steel containing by mass% of 0.6-1.2% carbon, 0.15-1% silicon, 0.3-1.5% manganese, 0.1-2% chromium, 0.1-2% vanadium, and dispersing vanadium carbides having 50-300nm grain diameter and having ≤12μm average grain diameter in the original austenitic crystal grain. Further, nitrogen-enriched layer is formed in the surface layer part, and the retained austenite quantity in the surface layer part is 20-40 vol%, and the rolling surface of the outer ring, the rolling surface of the inner ring and the outer peripheral surface of the tapered roller 17, have ≥59 HRC hardness.;COPYRIGHT: (C)2007,JPO&INPIT