SURF HARD is a nitriding alloy steel designed for those applications requiring exceptionally hard wear resistant surface and a tough core, such as heavy duty gears, spline shafts, rubber and paper mill rolls, cylinder liners, etc. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness and fatigue. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-246. Producer or source: Atlas Alloys Division, Rio Algom Corporation.