Alloy 400 is a nickel copper alloy, with a typical composition of:
Alloy 400 is a solid solution binary alloy which has a face-centred cubic lattice structure.
Alloy 400 is predominantly used in the marine and chemical processing industries, typical applications being valves, diaphragms, springs and heat exchangers. The alloy exhibits very low corrosion rates in seawater, and is also resistant to stress corrosion cracking in fresh water. It displays strong resistance to hydrofluoric acid in all concentrations, as well as many forms of sulphuric and hydrochloric acids. It is suited to both high and low temperature applications, displaying excellent mechanical properties at sub zero temperatures. In fact, strength and hardness improve at very low temperatures and does not become brittle in contrast to many ferrous materials. Alloy 400 also remains ductile and shows tough fracture characteristics at low temperatures. A key property of alloy 400 is its strength over a large range of temperatures. It retains strength up to and including 1000°F.
Werkstoff 2.4360, 2.4361.
ASTM B 127
Monel® 400 is a trademark of Special Metals Corporation group of companies.