Patent ID: 11078559

Abstract:
A steel alloy for bearings contains: 0.6 to 0.9 wt. % carbon, 0.1 to 0.5 wt. % silicon, 0.1 to 1.5 wt. % manganese, 1.5 to 2.0 wt. % chromium, 0.2 to 0.6 wt. % molybdenum, 0 to 0.25 wt. % nickel, 0 to 0.3 wt. % copper, 0 to 0.2 wt. % vanadium, 0 to 0.2 wt. % cobalt, 0 to 0.2 wt. % aluminium, 0 to 0.1 wt. % niobium, 0 to 0.2 wt. % tantalum, 0 to 0.05 wt. % phosphorous, 0 to 0.03 wt. % sulphur, 0 to 0.075 wt. % tin, 0 to 0.075 wt. % antimony, 0 to 0.075 wt. % arsenic, 0 to 0.01 wt. % lead, up to 350 ppm nitrogen, up to 100 ppm oxygen, up to 50 ppm calcium, up to 50 ppm boron, up to 50 ppm titanium, the balance being iron, together with any other unavoidable impurities. Furthermore, the steel alloy contains (i) molybdenum and silicon in a weight ratio of 0.4<Mo/Si<6.0 and (ii) molybdenum and chromium in a weight ratio of 0.1<Mo/Cr<0.4.