Monel Nickel-Copper Alloy

Monel is a nickel-copper alloy that is especially resistant to saltwater and acids. When welding, you need to make sure to keep the heat input low and let the weld cool slowly. If you cool too quickly, the structure becomes hard and brittle, and the weld will crack. Best to use matching Monel filler and keep the interpass temperature low, then the part will be clean and tight.