| 摘要 |
<p>Disclosed is a martensitic stainless steel for heat-resistant disc brakes which is excellent in hardenability and can be easily quench hardened at relatively low temperatures while maintaining high heat resistance. This martensitic stainless steel for heat-resistant disc brakes is characterized by having a composition consisting of, in mass%, 0.05-0.10% of C, not less than 0.1% and not more than 1% of Si, 0.2-2.0% of Mn, not more than 0.04% of P, not more than 0.010% of S, 0.010-0.025% of N, 11-14% of Cr, 0.5-2% of Ni, 0.5-2% of Cu, 1-2% of Mo, 0.03-0.3% of Nb, not more than 0.01% of Al, not more than 0.1% of Ti and the balance of Fe and unavoidable impurities while satisfying that C + N is 0.06-0.1%. This martensitic stainless steel for heat-resistant disc brakes is also characterized in that ?p obtained by the formula (1) below is not less than 80. ?p = 420[%C] + 470[%N] + 23[%Ni] + 9[%Cu] + 7[%Mn] - 11.5[%Cr] - 11.5[%Si] -52[%Al] - 12[%Mo] - 47[%Nb] + 189 (1)</p> |
