| 摘要 |
PURPOSE: To produce a long life induction hardened bearing steel capable of manufacturing bearing parts excellent in rolling fatigue characteristics at a low cost by specifying a composition consisting of C, Si, Mn, S, Al, N, Mg, P, Ti, O, and Fe. CONSTITUTION: This steel is a long life induction hardened bearing steel having a composition which consists of, by weight, 0.45-O.70% C, 0.05-1.70% Si, 0.35-2.0% Mn, 0.001-0.03% S, 0.010-0.07% Al, 0.003-0.015% N, 0.0005-0.0300% T.Mg and the balance iron with inevitable impurities, and further contains, if necessary, 0.05-1.20% Mo and further one or more kinds among 0.03-1.50% Cr, 0.10-2.00% Ni, 0.03-0.7% V, 0.005-0.3% Nb, and 0.0005-0.005% B and in which the contents of P, Ti, and T.O are limited to <=0.025%, <=0.0040% and 0.0020%, respectively. This steel can be suitably used for bearing parts. Further, it is preferable that the ratio, by number, of contained oxides in this steel satisfies inequality [(the number of MgO.Al2 O3 )+(the number of MgO)]/(the number of all oxide inclusions)>=0.80. |
