NiFe 55/45 alloy is suitable for welding all grades of cast iron but particularly for spheroidal graphite (SG), nodular or ductile irons and some alloy cast irons. It provides compatible strength, ductility and toughness, coupled with good machinability. The NiFe consumables can also be used on some of the high alloy austenitic irons (Ni-Resist). The flake graphite grades are welded with a preheat of 300-350℃ but the SG grades are best buttered using low heat input, and low temperature techniques to avoid HAZ hot cracking. Note the martensitic Ni-Hard cast irons and white irons are generally considered to be unweldable because they are too crack-sensitive. The NiFe consumables are also suitable for welding transition joints between cast iron and cast steels, and cast iron and mild/low alloy steels. Typical components are machine bases, pump bodies, engine blocks, gears and transmission housings.

GRADE AND MAIN CHEMICAL COMPOSITION (%)

MINIMUM MECHANICAL PROPERTIES

WELDING PARAMETERS/PACKING