| 摘要 |
A stainless steel for a brake disc less susceptible to the deterioration of material properties, especially the deterioration of hardness, when heated to a temperature exceeding 500 DEG C during braking, while maintaining abrasion resistance, rusting resistance and toughness of a conventional steel, is provided. A stainless steel for a brake disc excellent in resistance to temper softening, characterized in that: said steel contains, in terms of wt%, C: 0.01 to 0.1%, N: 0.03% or less, C+N: 0.04 to 0.1%, Si: 1% or less, Mn: 2% or less, Ni: less than 0.5%, Cr: 10 to 15%, and Nb: 0.02 to 0.5%, with the balance Fe and unavoidable impurities; that the hardness after quenching heat treatment is in the range of 30 to 40 HRC; and that the temper softening temperature for lowering the hardness to below 30 HRC is at least 530 DEG C. Further, it is desirable to add at least one of the following elements; 0.1 to 2% of Cu, 0.1 to 1% of Mo, 0.01 to 0.5% of Ti, 0.01 to 0.5% of V or 0.0005 to 0.01% of B, and to make the value of gamma P calculated from steel chemical composition at least 70%. <IMAGE>
|
