Monel

Monel is a group of nickel alloys, primarily composed of nickel (up to 67%) and copper, with small amounts of iron, manganese, carbon, and silicon. Stronger than pure nickel, Monel alloys are resistant to corrosion by many agents, including rapidly flowing seawater. They can be fabricated readily by hot- and cold-working, machining, and welding.

Monel was created by David H. Browne, chief metallurgist for International Nickel Co. Monel alloy 400 is a binary alloy of the same proportions of nickel and copper as is found naturally in the nickel ore from the Sudbury (Ontario) mines and is therefore considered a puritan alloy. Monel was named after company president Ambrose Monell, and patented in 1906. One L was dropped, because family names were not allowed as trademarks at that time. The name is now a trademark of Special Metals Corporation.

It is a very expensive alloy, with cost ranging from 5 to 10 times the cost of copper and nickel, hence its use is limited to those applications where it cannot be replaced with cheaper alternatives. Compared to carbon steel, piping in Monel is more than 3 times as expensive.