Nickel alloy 2.4360 (Alloy 400) is a nickel-copper alloy with exceptional resistance to seawater and hydrofluoric acid, offering moderate strength and toughness for marine and chemical equipment.
2.4360 (Alloy 400 or Monel 400) is a nickel-copper alloy (about 63% nickel, 28–34% copper) with exceptional resistance to flowing seawater, steam, alkalis, and hydrofluoric acid.
It is moderately strong and tough when annealed but corrosion rates rise in aerated acids or with oxidizing salts, and it work-hardens rapidly, so machining is slow.
Nickel alloy 2.4360 is a good option for pump shafts, seawater valves, and marine and chemical-processing fittings.