For precision capillary tube of metal materials, we have been working on it for more than 30 years.

Precision metal foil and strip,Precision seamless tube,Profiled seamless tube
BackYou are in :  Home  >  Materials  >  Corrosion resistant alloy


Alloy 400

  • Material

    Alloy 400, UNS N04400, W.Nr.2.4360, 2.4361

  • Overview

    Alloy 400 is a single-phase, solid solution, nickel-copper alloy that can be hardened only by cold working. It has high strength and toughness over a wide temperature range and excellent resistance to many corrosive environments.

  • Character

    Alloy 400 is characterized by:

    Resistance against chloride-induced stress corrosion

    Excellent strength even at low application temperatures

    Easy processing compared to other high-alloy materials

    Approved for pressure vessels from -10 to 425°C (14 to 797°F) pursuant to VdTÜV Material Sheet 263 and up to 480°C (896°F) in accordance with ASME Boiler and Pressure Vessel Code. 

  • Application

    Alloy 400 is widely used in many fields, especially marine and chemical processing. Typical applications are valves and pumps; pump and propeller shafts; marine fixtures and fasteners; electrical and electronic components; springs; chemical processing equipment; gasoline and fresh water tanks; crude petroleum stills, process vessels and piping; boiler feedwater heaters and other heat exchangers; and deaerating heaters.

  • Chemical Composition (wt% as per ASTM B165)






    Alloy 400










    Alloy 400





  • Mechanical Property

    Alloy 400 in annealed condition as per ASTM B165


    Tensile strength

    ksi (MPa)

    Yield strength at

    0.2 offset ksi (MPa)

    Elongation in 2”

    % min.

    Reduction of area

    % min.

    Alloy 400

    ≥70 (480)

    ≥28 (195)


  • Corrosion Resistance

    Alloy 400 has excellent resistance to neutral and alkaline salts and has long been the standard material for salt production systems. Alloy 400 is one of the few materials which can be used in contact with fluorine, hydrofluoric acid and hydrogen fluoride or their compounds. The material has a very high resistance to alkaline media. Its behavior in seawater is also excellent compared to copper-based alloys with an increased resistance to cavitation. Alloy 400 can be used in contact with highly diluted mineral acids, such as sulfuric and hydrochloric acid, provided that they are not ventilated.

    Since the alloy does not contain chromium, the corrosion rates can increase significantly under oxidizing conditions. While Alloy 400 is resistant to stress corrosion cracking, it can display stress cracks in the presence of mercury or in moist, aerated HF vapors. Stress relief annealing is necessary in these conditions.

    Alloy 400 exhibits resistance to corrosion by many reducing media. It is also generally more resistant to attack by oxidizing media than higher copper alloys. This versatility makes alloy 400 suitable for service in a variety of environments.

    Alloy 400 is widely used in marine applications. While alloy 400 products exhibit very low corrosion rates in flowing seawater, stagnant conditions have been shown to induce crevice and pitting corrosion. Alloy 400 is also resistant to stress corrosion cracking and pitting in most fresh and industrial waters.

    Alloy 400 offers exceptional resistance to hydrofluoric acid in all concentrations up to the boiling point. It is perhaps the most resistant of all commonly used engineering alloys. Alloy 400 is also resistant to many forms of sulfuric and hydrochloric acids under reducing conditions.

  • Available Process

    (1) Hot formed, annealed, descaled

    (2) Cold worked and bright annealed

    (3) Cold worked, bright annealed, polished (MP, EP, CP etc.)

  • Common Tests

    Chemical composition






    Micro structure



    Intergranular Corrosion

    Surface condition

    Shape and dimension

    Positive Material Identification

  • Product Forms


    Size range

    Capillary tube

    OD 0.15 ~ 6.0 mm

    WT 0.015 ~ 1.5 mm

    Thin wall & Ultra thin wall seamless tube

    OD6.0 ~80.0 mm

    WT 0.05 ~4.5 mm

    Micro ID and heavy thick wall seamless tube

    OD3.0 ~50.0 mm

    ID 0.30 ~5.0 mm

    Precision conic seamless tube

    Bigger end: OD3.0 - 426.0mm

    Smaller end: OD2.5 - 346.0mm

    WT: 0.15 - 40.0mm

    HP /UHP BA+ tube

    EP tube

    OD 1.0 ~ 76 mm

    WT 0.10 ~ 10.0 mm

    Small caliber precision seamless tube

    OD6.0 ~89 mm

    WT 0.50 ~9.0 mm

    Profiled seamless tube

    Build to drawing

    Build to specification

We use cookies to offer a better browsing experience, analyze site traffic, and personalize content. By using this site, you agree to our use of cookies.