Monel 400
Material Data Sheet
Monel 400 is a nickel-copper alloy (approximately 67% nickel - 23% copper) that is resistant to high temperature seawater and steam, as well as salt and corrosive solutions. Monel 400 is a solid solution alloy that can only be hardened by cold working. This nickel alloy has good corrosion resistance, wear resistance, and high strength. Monel 400 has a low corrosion rate in fast-flowing saltwater or seawater, excellent resistance to stress corrosion cracking in most freshwaters, and tolerance to a wide range of corrosive conditions, making it widely used in marine and other non-oxidizing chloride solutions. This nickel alloy is particularly resistant to hydrochloric and hydrofluoric acids after degassing. Due to the high copper content, Monel 400 is quickly attacked by nitric acid and ammonia systems.
Monel 400 has good mechanical properties in sub-zero temperatures, can be used up to 1000 degrees Fahrenheit, and has a melting point of 2370-2460 degrees Fahrenheit. However, Alloy 400 is weaker in the annealed condition, so a wide range of temperatures can be used to improve strength.
Monel 400 is easily welded using the gas tungsten arc, gas metal arc, or shielded metal arc processes with appropriate filler metals. Post-weld heat treatment is not required, but for optimum corrosion resistance, thorough cleaning after welding is essential, otherwise there is a risk of contamination and embrittlement. Finished products with a wide range of mechanical properties can be produced, provided the amount of hot or cold work is properly controlled, and the appropriate heat treatment method is selected.
Like most other nickel alloys, Monel 400 is generally difficult to machine and will work harden. However, excellent results can be achieved with the correct choice of tools and machining methods.
chemical composition of Monel 400
| Element | Content (% max, unless specified) |
|---|---|
| Nickel (Ni) | 64.0 (min) |
| Copper (Cu) | 31.0 |
| Iron (Fe) | ≤ 2.5 |
| Manganese (Mn) | ≤ 2.0 |
| Silicon (Si) | ≤ 0.5 |
| Carbon (C) | ≤ 0.3 |
| Sulfur (S) | ≤ 0.02 |
physical properties of Monel 400
| Property | Metric | Imperial |
|---|---|---|
| Density | 8.8 g/cm³ | 0.318 lb/in³ |
| Melting Point | 1300–1350 °C | 2370–2460 °F |
mechanical properties of Monel 400
| Property | Metric | Imperial |
|---|---|---|
| Tensile Strength (Annealed) | 517–620 MPa | 75–90 ksi |
| Yield Strength | 172–345 MPa | 25–50 ksi |
| Elastic Modulus | 179 GPa | 26,000 ksi |
| Poisson's Ratio | 0.32 | 0.32 |
Applications
Marine Engineering
Chemical and Hydrocarbon Processing Equipment
Gasoline and Fresh Water Tanks
Crude Oil Stills
Degassing Heaters
Boiler Feedwater Heaters and Other Heat Exchangers
Valves, Pumps, Shafts, Fittings and Fasteners
Industrial Heat Exchangers
Chlorinated Solvents
Crude Oil Stills
Specifications
AMS 4574
AMS 4675
AMS 4731
ASTM B163
ASTM B165
ASTM F96
UNS N04400
