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)