AutomotiveMarine & DefenceMonel Alloy 400Oil & Gas

Alloy 400 (UNS designation N04400) is a nickel copper solid solution alloy with small additions of manganese, silicon and iron to enhance the grade’s strength and corrosion resistance. It exhibits high strength over a wide temperature range.
Alloy 400 has excellent resistance to a variety of corrosive environments from mildly oxidizing through neutral and in moderately
reducing conditions. Alloy 400 also performs well in marine and other nonoxidizing chloride solutions. Alloy 400 is also particularly
resistant to stress-corrosion cracking and pitting corrosion in most fresh and industrial waters.
As it is with commercially pure nickel, Alloy 400 is low in strength in the annealed condition and it is consequently offered in
a variety of tempers which increase the strength of the material. Alloy 400 can only be hardened by cold working.
Columbia Metals is a leading supplier and distributor of Alloy 400 in cold worked and stress relieved condition as standard,
to ensure the maximum mechanical strength, the optimum machinability and best surface condition for the ultimate application.
Monel® 400 (N04400) Standards & Specifications
Alloy 400 is released against the British standard BS3076 as NA13 and against the American standard ASTM B164 as UNS N04400. The use of the term Monel relates to a trademarked alloy first developed in 1905, the President of the International Nickel Company at that time being Ambrose Monell. The use of the ASTM and BS specifications and the term Alloy 400 can be seen as equivalent alloys to Monel® 400.
Corrosion Resistance
Alloy 400 exhibits exceptional corrosion resistance to hydrofluoric acid and many reducing media and it performs better against oxidising media than high copper alloys. It is one of only a few alloys that can be used in contact with fluorine and hydrogen fluoride. Alloy 400 is also highly resistant to many forms of sulphuric and hydrochloric acids under reducing conditions, as well as alkalis. Alloy 400 is also resistant to stress corrosion cracking and pitting in most fresh and industrial waters, as well as having excellent corrosion resistance in flowing seawater, making it widely utilised in chemical and marine engineering applications.
Applications
Offshore & Marine
Marine fixtures and fasteners, propellers, pump and propeller shafts, splash zone sheathing
Chemical Processing
Chemical processing equipment, components for the manufacture of chlorinated solvents, salt production, ethyl chloride purification, hydrochloric acid production, hydrofluoric acid and sulphuric acid process industry, brine heaters.
Chemical Composition
Alloy 400 was one of the first nickel alloys, mined from the original nickel-copper ore in Canada in the late 19th century. The composition of the original ore is roughly the same as the composition of Alloy 400 today.
Ni+Co | Cu | Fe | Mn | Si | C | S | Al | P |
63.00 max | 28.0-34.0 | 2.50 max | 2.00 max | 0.50 max | 0.30 max | 0.024 max | 0.02 max | 0.005 max |
Alloy 400 high strength and toughness is maintained over a wide range of temperatures up to 400 ℃. There is an increase in strength and hardness at sub-zero temperatures with only a slight decrease in elongation. Monel 400 has excellent mechanical properties at subzero temperatures. With no ductile to brittle transition down even to cryogenic temperatures Alloy 400 is suited to many applications where ferrous metals cannot be used.
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.
Monel Alloy 400 | ||
Related Specifications | Mechanical Properties |
Alloy Name | BS | UNS | BS EN | Others | Ultimate Tensile Strength N/mm² | Minimum Yield Strength N/mm² | Elongation % | Hardness HB | |
Monel Alloy 400 | NA13 | N04400 | BS3076 | 480-600 | 170-415 | 20-35 | 35 HRC max |
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