Alloy 400

Alloy 400, commonly known as MONEL®, is a Nickel-Copper alloy, resistant to sea water and steam at high temperatures as well as to salt and caustic solutions. It is characterized by good general corrosion resistance, good weldability and moderate to high strength. The alloy has been used in a variety of applications. It has excellent resistance to rapidly flowing brackish water or seawater. It is particularly resistant to hydrochloric and hydrofluoric acids when they are de-aerated. The alloy is slightly magnetic at room temperature. Alloy 400 is widely used in the chemical, oil and marine industries.

UNS: N04400
Stock Sizes: 1/8” – 1” OD


  • Seamless Tube: ASTM B163/B165
  • NACE MR0175/MR0103

Available Processing:

  • Cold Worked and Bright Annealed

Common Testing: Eddy Current, Flare, Flattening, Positive Material Identification

Chemical Composition (%)

Iron (Fe)2.5% Max
Nickel (Ni)63%
Manganese (Mn)2% Max
Silicon (Si)0.5% Max
Copper (Cu)28-34%
Carbon (C)0.3% Max
Sulfur (S)0.024% Max

Physical Properties

Density (lb/in3)0.318
Elongation (min %)35
Minimum Yield (psi)28,000
Minimum Tensile (psi)70,000
Max Hardness (HRB)75