Monel 400
Monel 400 – Nickel-Copper Alloy Resistant to Hydrofluoric Acid, Seawater, and Alkaline Solutions
Monel 400 is a solid-solution Ni-Cu alloy (66% Ni / 31.5% Cu) providing unmatched corrosion resistance in hydrofluoric acid, seawater, and alkaline solutions. It is one of the few materials capable of handling HF acid at all concentrations below 85°C, making it irreplaceable in fluorine and hydrofluoric acid processing equipment and marine valve systems.
Key Properties
- Tensile Strength: 552 MPa
- Hardness: 120 HB
- Composition: 66% Ni / 31.5% Cu
- Unique Resistance: HF acid (all concentrations to 85°C), seawater, alkaline solutions
- Density: 8.83 g/cm³
- Standards: ASTM B127 / AMS 4544
Common Applications
HF acid processing equipment and piping, marine valves and pumps, feedwater heaters, chemical plant heat exchangers, petroleum refinery components, and naval hardware in aggressive service environments.
Material properties
| Material name | Monel 400 |
|---|---|
| Type | Nickel Alloys |
| Standard code | ASTM B127 / AMS 4544 |
| Tensile strength (MPa) | 552 |
| Yield strength (MPa) | 240 |
| Fatigue strength (MPa) | 240 |
| Elongation (%) | 35 |
| Hardness (Brinell) | 120 |
| Density (g/cm³) | 8.83 |
| Electrical resistivity (µΩ·in) | 54.7 |
| Thermal conductivity (W/m·K) | 21.8 |
| Melting range (°C) | 1300–1350 |
| Weldability | Excellent |
| Formability | Good |
| Shear modulus | 66 |
| Industry code | monel |