Monel 400 alloy is a nickel copper alloy which has high strength over a wide temperature range up to 1000 F. It is regarded as being a ductile Nickel-Copper alloy with resistance to a wide variety of corrosive conditions. This alloy is most frequently applied in a range of environments going from mildly oxidizing through neutral and to moderately reducing conditions. Additional application area of this material is in marine environments and other non-oxidizing chloride solutions. Like with commercially pure Nickel, Monel® 400 is low in strength in the annealed condition, for this reason a variety of tempers are used to achieve higher strength levels. Monel 400 is one of the few alloys that maintains its strength in sub-zero or cryogenic temperatures, so it is often used in those applications.
The chemical composition of MONEL 400 alloy is given in the following table.
| Element | Content (%) |
| Nickel, Ni | Remainder |
| Copper, Cu | 28-34 |
| Iron, Fe | 2.5 max |
| Manganese, Mn | 2 max |
| Silicon, Si | 0.5 max |
| Carbon, C | 0.3 max |
| Sulphur, S | 0.024 |
| Grade | UNS | DIN | EN | AMS | ASTM | JIS | |
| Monel 400 | N04400 |
|
2.4360 2.4361 |
AMS 4574
AMS 4675
AMS 4731
|
ASTM B163
ASTM B165
ASTM F96
|
- | |
The mechanical properties of MONEL 400 alloy are tabulated below.
| properties | Metric | Imperial |
| Tensile strength(annealed) | 517-620 MPa | 75-90 ksi |
| Yield strength | 172-345 MPa | 25-50 ksi |
| Modulus of elasticity | 179 GPa | 26000 ksi |
| Poisson's ratio | 0.32 | 0.32 |