Patent ID: 6248186
Filing Date: 2001-06-19
Classification: C21D,C22C,F16C,Y10S

Abstract:
A ball-and-roller bearing which exhibits an excellent corrosion resistance, comprising:an inner ring;an outer ring arranged on the co-axis of the inner ring and rotating around the axis relative to the inner ring; anda rolling body interposed between the inner ring and the outer ring and rolling on the inner ring and the outer ring in accordance with rotation of the outer ring relative to the inner ring,wherein at least one member selected from the group consisting of the inner ring, the outer ring, and the rolling body comprises a core member consisting essentially of an alloy consisting essentially of iron, 0.15% by weight or less of carbon, at least one of 0.2 to 1.0% by weight of silicon and 0.2 to 1.5% by weight of manganese, 7.0 to 11.0% by weight of chromium, 1.5 to 6.0% by weight of molybdenum, 0.5 to 8.0% by weight of cobalt, 1.0% by weight or less of vanadium, and 5.0% by weight or less of nickel, and a case hardened layer formed by subjecting a surface region of said core member to a secondary hardening treatment and containing 0.9 to 1.5% by weight of carbon.