Nickel alloys have a low thermal conductivity, resist scaling and oxidation at elevated temperatures, and do not harden without special effort and technique. Even when faced with multiple heating and cooling cycles they retain these properties.
Things to be aware of when welding with nickel and nickel alloys:
High-nickel alloys are designed to withstand highly corrosive environments most generally associated with high-pressure environments and elevated temperatures. You’ll frequently find them used in oil and gas, aerospace, and power-generating industries for joining and cladding. Nickel alloys with higher percentages of copper, (CuNi-Gen 413 or NiCu-Gen 418, for instance) are often used to fabricate hardware in marine, chemical, and desalination construction.
They can be used with most welding processes, and CWI (Central Wire Industries) Welding Generation4 manufactures an assortment of nickel-based and high nickel welding consumables for TIG, MIG, SAW, and SMAW processes.