Monel 400

Monel 400


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.
monel500

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.

In what form is Monel 400 Available at Micrometals

  • Sheet
  • Plate
  • Bar
  • Wire
  • Pipe & Tube (welded & seamless)
  • Fittings (i.e. flanges, slip-ons, blinds, weld-necks, lapjoints, long welding necks, socket welds, elbows, tees, stub-ends, returns, caps, crosses, reducers, and pipe nipples)

Chemical Composition, %

C Mn S Si Ni Cu Fe
.30 max 2.00 max .024 max .50 max 63.0 min 28.0-34.0 2.50 max

ASTM Specifications

Pipe Smls Pipe Welded Tube Smls Tube Welded Sheet/Plate Bar Forging Fitting Wire
B165 B725 B163 B127 B164 B564 B366

Mechanical Properties

Typical room temperature Tensile Properties of Annealed Material

Product Form Condition Tensile (ksi) .2% Yield (ksi) Elongation (%) Hardness (HRB)
Rod & Bar Annealed 75-90 25-50 60-35 60-80
Rod & Bar Cold-Drawn Stress Relieved 84-120 55-100 40-22 85-20 HRC
Plate Annealed 70-85 28-50 50-35 60-76
Sheet Annealed 70-85 30-45 45-35 65-80
Tube & Pipe Seamless Annealed 70-85 25-45 50-35 75 max *