Copper-nickel alloy welding rods are designed for welding copper alloys with a nickel content of 10 to 30% (copper-nickel), such as 90% Cu + 10% Ni, 80% Cu + 20% Ni, or 70% Cu + 30% Ni; some types may be doped with Fe and Mn. To reduce the risk of porosity, these rods are doped with a small amount of Ti. To reduce the possibility of solidification cracking, the silicon content in the rods is limited. The thermal conductivity of these alloys is similar to that of low-carbon steel, therefore no preheating is required.
These rods are used to weld these alloys with nickel alloys of groups 400 and 500 (Monel), to create a transition layer on edges when welding different material combinations, and to create a corrosion-resistant layer on steel. When hardfacing steel, excessive iron contamination in the molten weld pool should be avoided. The resulting metal exhibits high corrosion resistance in seawater and relatively high strength properties.
Its main applications include desalination plants and offshore structures. Typically, pure argon is used as a shielding gas, but argon-hydrogen mixtures are preferred because they improve weld pool flow and produce a cleaner weld surface.


