Abstract: An iron composition and method for processing the composition that produces a steel alloy having enhanced low temperature toughness, without compromising other desirable mechanical properties, is described. The composition can be used to produce devices, such as saw chain, particularly useful for low temperature applications. In general, the steel composition comprises from about 0.2 weight percent to about 0.4 weight percent nickel, from about 0.2 to about 0.4 weight percent chromium, from about 0.5 weight percent to about 1.0 weight percent carbon, from about 0.3 to about 0.5 weight percent manganese, from about 0.1 to about 0.35 weight percent silicon, and from about 0.08 weight percent to about 0.20 weight percent molybdenum. After heat treating, the steel composition has an average fracture toughness of greater than about 42 ksi in.sup.1/2, and an average modified Charpy energy-to-failure of greater than about 2 ft.lbs at temperatures greater than about -20.degree. F.

Abstract: An iron composition and method for processing the composition that produces a steel alloy having enhanced low temperature toughness, without compromising other desirable mechanical properties, is described. The composition can be used to produce devices, such as saw chain, particularly useful for low temperature applications. In general, the steel composition comprises from about 0.2 weight percent to about 0.4 weight percent nickel, from about 0.2 to about 0.4 weight percent chromium, from about 0.5 weight percent to less than about 1.0 weight percent carbon, from about 0.3 to about 0.5 weight percent manganese, and from about 0.08 weight percent to about 0.20 weight percent molybdenum. After heat treating, the steel composition has an average fracture toughness of greater than about 42 ksi in.sup.1/2, and an average modified Charpy energy-to-failure of greater than about 2 ft.lbs at temperatures greater than about -20.degree. F.