Abstract: A carburizing alloy steel and case-hardened articles made therefrom, having high core impact strength and fracture toughness combined with high case hot hardness and temper resistance at 400.degree. F. (204.degree. C.), containing 0.06-0.16% carbon, 0.2-0.7% manganese, 0.5-1.5% silicon, 0.5-1.5% chromium, 1.5-3% nickel, 1-4% copper, 2.5-4% molybdenum, up to 0.4% vanadium, and the balance iron and incidental impurities. The alloy may also contain small amounts of phosphorus, sulfur, nitrogen, aluminum, columbium, titanium, zirconium, and calcium.

Abstract: A low alloy temper resistant saw blade steel containing about 0.90-1.4% carbon, 0.8-2% silicon, 0.5-1.5% vanadium, 1-3% tungsten plus twice the percent molybdenum, and the balance iron plus incidental impurities having a minimum hardness of Rc 60 in its hardness and tempered condition and which is not softened by exposure to temperatures of about 600.degree. F. A process for preparing the steel is also disclosed in which the alloy is hot worked to strip which is then austenitized, isothermally transformed at least in part to bainite, and subjected to a subcritical anneal to form a pinpoint carbide structure with hardness reduced sufficiently to facilitate fabrication of the saw teeth. After the saw teeth are formed and set, the heat treatment is completed by flame hardening the teeth and tempering so that the teeth are at a minimum hardness of about Rc 60 and do not soften when exposed to temperatures of about 600.degree. F.

Abstract: An alloy steel is provided containing, by weight percent, carbon 0.5-1.1, manganese 0.10-<0.50, silicon 0.10-<0.80, chromium 3.5-5.0, molybdenum 2.5-5.0, vanadium 0.5-2.0, cobalt 0.5-4.0, columbium 0.15-0.50, up to 0.10 aluminum and the balance iron except for incidental impurities. The alloy can be balanced to provide a minimum room temperature hardness of R.sub.c 60 with outstanding toughness and ductility or to provide a minimum room temperature hardness of R.sub.c 63 with good wear resistance and toughness.