STAINLESS STEEL BRAKE DISC AND METHOD FOR PRODUCTION THEREOF

摘要

The present invention is directed to a stainless steel brake disc which is excellent in toughness, corrosion resistance, and wear resistance, and comprises, in % by mass, 0.030 to 0.080% of C, 0.05% to 1.0% of Si, 1.0 to 1.5% of Mn, 0.035% or less of P, 0.015% or less of S, 11.0 to 14.0% of Cr, 0.01 to 0.50% of Ni, 0.001 to 0.15% of V, less than 0.1% of Nb, 0.05% or less of Ti, 0.05% or less of Zr, 0.05% or less of Al, 0.015 to 0.060% of N, 0.0002% or more and 0.0050% or less of B, and 0.0080% or less of O, wherein an AT value of equation 1 is 0.055 to 0.090, equation 2 is satisfied, a ferrite phase fraction, in which an IQ value of an EBSD pattern is 4,000 or more, is 1% to 15%, a Charpy impact value is 50 J/cm2 or more, and hardness is 32 to 38 HRC.;C+0.8(N−B)  (1);PV=1.2Ti+0.8Zr+Nb+1.1Al+O≦0.1  (2)

主权项

1. A stainless steel brake disc comprising, in % by mass, 0.030 to 0.080% of C, 0.05% to 1.0% of Si, 1.0 to 1.5% of Mn, 0.035% or less of P, 0.015% or less of S, 11.0 to 14.0% of Cr, 0.01 to 0.50% of Ni, 0.001 to 0.15% of V, 0.10% or less of Nb, 0.05% or less of Ti, 0.05% or less of Zr, 0.05% or less of Al, 0.015 to 0.060% of N, 0.0002% or more and 0.0050% or less of B, and 0.0080% or less of O, wherein an AT value of equation 1 is 0.055 or more and 0.090 or less, equation 2 is satisfied, the balance is Fe and inevitable impurities, a ferrite phase fraction, defined by the fact that an image quality value of an EBSD pattern is 4,000 or more, is 1% or more and 15% or less, and surface hardness is 32 HRC or more and 38 HRC or less:
AT=C+0.8(N−B)  (1) PV=1.2Ti+0.8Zr+Nb+1.1Al+O≦0.1  (2)where N, B, Ti, Zr, Nb, Al, and O in equation 1 and equation 2 each means the element content (% by mass).