Home > Monel Alloy Pipes & Tubes>Monel Alloy 400 Pipes & Tubes

Monel Alloy 400 Pipes & Tubes

Material Description

UNS N04400

Chemical Composition, %








.30 max

2.0 max

.024 max

.50 max

63.0 min


2.50 max

Monel 400 is a nickel-copper alloy (about 67% Ni – 23% Cu) that is resistant to sea water and steam at high temperatures as well as to salt and caustic solutions. Alloy 400 is a solid solution alloy that can only be hardened by cold working. This nickel alloy exhibits characteristics like good corrosion resistance, good weldability and high strength. A low corrosion rate in rapidly flowing brackish or seawater combined with excellent resistance to stress-corrosion cracking in most freshwaters, and its resistance to a variety of corrosive conditions led to its wide use in marine applications and other non-oxidizing chloride solutions. This nickel alloy is particularly resistant to hydrochloric and hydrofluoric acids when they are de-aerated.

As would be expected from its high copper content, alloy 400 is rapidly attacked by nitric acid and ammonia systems.

Monel 400 has great mechanical properties at subzero temperatures, can be used in temperatures up to 1000° F, and its melting point is 2370-2460° F. However, alloy 400 is low in strength in the annealed condition so, a variety of tempers may be used to increase the strength.


● Corrosion resistance in an extensive range of marine and chemical environments. From pure water to non-oxidizing mineral acids, salts and alkalis.

● This alloy is more resistant to nickel under reducing conditions and more resistant than copper under oxidizing conditions, it does show however better resistance to reducing media than oxidizing.

● Good mechanical properties from subzero temperatures up to about 480C.

● Good resistance to sulfuric and hydrofluoric acids. Aeration however will result in increased corrosion rates. May be used to handle hydrochloric acid, but the presence of oxidizing salts will greatly accelerate corrosive attack.

● Resistance to neutral, alkaline and acid salts is shown, but poor resistance is found with oxidizing acid salts such as ferric chloride.

● Excellent resistance to chloride ion stress corrosion cracking.


● Feed water and steam generator tubing.

● Brine heaters, sea water scrubbers in tanker inert gas systems.

● Sulfuric acid and hydrofluoric acid alkylation plants.

● Pickling bat heating coils.

● Heat exchanger tubing in a variety of industries.

● Transfer piping from oil refinery crude columns.

● Plant for the refining of uranium and isotope separation in the production of nuclear fuel.

● Pumps and valves used in the manufacture of perchlorethylene, chlorinated plastics.

● Monoethanolamine (MEA) reboiling tube.

● Cladding for the upper areas of oil refinery crude columns.

● Propeller and pump shafts

Seamless Tube Information

Specification: ASTM B-163 / ASME SB-163, ASTM B-165 / ASME SB-165

Outside Diameter: 6.0-114 mm

Wall Thickness: 0.5-15 mm

Length: Max.24000mm (the maximum length is for the scope of special diameters and walls)

Other sizes are on the request