Super Ni-Cast 55% nickel is the ultimate rod for all known grades of cast iron. Extra nickel content for crack-resistant, machinable welds. Great for joining heavy or thin sections to steel. The computer controlled coating produces welds that represent the optimum balance between tensile strength and machinability. Typical applications include welding grades 30, 40 and 50 gray cast irons - all thicknesses in all positions.