Patent ID: 7294212

Claim:
A high-strength stainless steel material in the form of a wheel rim consisting essentially of: a composition including less than 0.1% by mass of Cu, 0.1% by mass or more but less than 2.0% by mass of Mo, 0.0005% to 0.0050% by mass of B, 0.02% by mass or less of C, 1.0% by mass or less of Si, 2.0% by mass or less of Mn, 0.04% by mass or less of P, 0.01% by mass or less of S, 0.1% by mass or less of Al, 11% by mass or more but less than 17% by mass of Cr, 0.5% by mass or more but less than 3.0% by mass of Ni, and 0.02% by mass or less of N, so as to satisfy the following equations (1) through (4), 12≦Cr+Mo+1.5 Si≦17 (1) 1≦Ni+30(C+N)+0.5(Mn+Cu)≦4 (2) Cr+0.5(Ni+Cu)+3.3 Mo≧16.0 (3) 0.006≦C+N≦0.030 (4) wherein, the contents of C, B, N, Si, Mn, Cr, Mo, Ni and Cu are in % by mass, and the remainder essentially consisting of Fe; a structure including 12 to 95% by volume of martensite, and the remainder essentially consisting of ferrite, a tensile strength equal to or greater than 730 Mpa, and a weld-heat-affected zone toughness at −50° C. equal to or greater than 40 J/cm 2 wherein the wheel rim is incorporated into a wheel.