BEARING STEEL WITH EXCELLENT ROLLING FATIGUE CHARACTERISTICS, AND BEARING PARTS

摘要

Bearing steel material according to the present invention has: a properly adjusted chemical composition; an average chemical composition of oxide-inclusions which comprises 10 to 45% of CaO, 20 to 45% of Al 2 O 3 , 30 to 50% of SiO 2 , up to 15% (exclusive of 0) of MnO, and 3 to 10% of MgO, with the balance being unavoidable impurities; a maximum major axis diameter of the oxide inclusions in a longitudinal section of the steel material of 20 µm or less; and a spheroidal cementite structure.