Alloy 400 (Monel 400, UNS N04400 / 2.4360 / NiCu30Fe) is a high-strength, ductile nickel-copper alloy with broad corrosion resistance in seawater, hydrofluoric acid, sulfuric acid and alkaline media. Widely used in marine and chemical equipment such as pumps, valves, shafts, pipe fittings, fasteners and heat exchangers. Supplied as plates, bars, pipes, fittings and forgings.