BEARING STEEL MATERIAL WITH EXCELLENT ROLLING FATIGUE PROPERTY AND BEARING PART

摘要

A bearing steel material which contains 0.8-1.1 mass % C, 0.15-0.8 mass % Si, 0.1-1.0 mass % Mn, 1.3-1.8 mass % Cr, up to 0.05 mass % P (0 mass % is excluded), up to 0.015 mass % S (0 mass % excluded), 0.0002-0.005 mass % Al, 0.0002-0.0020 mass % Ca, 0.0005-0.010 mass % Ti, up to 0.0080 mass % N (0 mass % is excluded), and up to 0.0025 mass % O (0 mass % is excluded). The steel material contains oxide inclusions which have an average composition that comprises, in terms of mass %, 20-50% CaO, 20-50% Al2O3, 20-70% SiO2, and 3-10% TiO2.

主权项

1. A bearing steel material, comprising:
iron, from 0.8 to 1.1 mass % of C, from 0.15 to 0.8 mass % of Si, from 0.1 to 1.0 mass % of Mn, from 1.3 to 1.8 mass % of Cr, more than 0 mass % and 0.05 mass % or less of P, more than 0 mass % and 0.015 mass or less of S, from 0.0002 to 0.005 mass % of Al, from 0.0002 to 0.0020 mass % of Ca, from 0.0005 to 0.0050 mass % of Ti, more than 0 mass % and 0.0080 mass % or less of N, and more than 0 mass % and 0.0025 mass % or less of O, wherein the steel material comprises oxide inclusions, and the oxide inclusions comprise, on the mass % basis, from 20 to 50% of CaO, from 20 to 50% of Al2O3, from 20 to 70% of SiO2, and from 3 to 10% of TiO2.