Hangbo Alloy Group
Shanghai · Est. 2012
UNS N04400 / W.Nr. 2.4360 — The premier nickel-copper alloy for seawater corrosion resistance. Complete technical data for marine engineers and procurement professionals.
Monel 400 (UNS N04400 / W.Nr. 2.4360) is a nickel-copper alloy with approximately 67% nickel and 30% copper content. It is one of the most widely used nickel alloys due to its excellent combination of corrosion resistance, strength, and fabricability. Monel 400 is particularly renowned for its outstanding resistance to seawater, hydrofluoric acid, and alkaline environments. The alloy maintains excellent mechanical properties from sub-zero temperatures up to approximately 480°C (900°F). Its solid-solution strengthened structure provides excellent ductility and toughness, making it readily formable and weldable.
The chemical composition of Monel 400 is closely controlled to achieve its characteristic corrosion resistance and mechanical properties. The nickel-copper ratio is optimized for resistance to seawater and reducing acid environments.
| Element | Min % | Max % |
|---|---|---|
| Nickel (Ni) | 63.0 | Balance |
| Copper (Cu) | 28.0 | 34.0 |
| Iron (Fe) | — | 2.5 |
| Manganese (Mn) | — | 2.0 |
| Carbon (C) | — | 0.30 |
| Silicon (Si) | — | 0.50 |
| Sulfur (S) | — | 0.024 |
Monel 400 has a face-centered cubic (FCC) crystal structure, which provides excellent ductility and toughness at both room and cryogenic temperatures. The alloy's thermal and electrical conductivity are lower than copper but significantly higher than most stainless steels.
| Property | Value | Unit |
|---|---|---|
| Density | 8.83 | g/cm3 |
| Melting Point | 1350 | °C |
| Specific Heat (21°C) | 427 | J/kg·K |
| Thermal Conductivity (21°C) | 21.8 | W/m·K |
| Electrical Resistivity (21°C) | 0.51 | μΩ·m |
| Modulus of Elasticity (21°C) | 179.5 | GPa |
| Mean Coefficient of Thermal Expansion (21-93°C) | 13.9 | μm/m·°C |
| Curie Temperature | 50 | °C |
The mechanical properties of Monel 400 depend on the degree of cold working and heat treatment. The data below represents typical values for hot-finished and annealed bar per ASTM B164.
| Property | Hot-Finished | Cold-Drawn |
|---|---|---|
| Tensile Strength | 550 MPa (80 ksi) | 690 MPa (100 ksi) |
| Yield Strength (0.2% offset) | 240 MPa (35 ksi) | 550 MPa (80 ksi) |
| Elongation in 2 inches | 35% | 22% |
| Hardness (Rockwell B) | 65-75 HRB | 85-95 HRB |
Monel 400 maintains good strength at moderate temperatures but is not typically used for high-temperature applications above 480°C (900°F) due to oxidation and loss of strength. The alloy is ideal for applications requiring good mechanical properties at sub-zero and moderate temperatures.
| Temperature (°C) | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) |
|---|---|---|---|
| 21 (Room) | 550 | 240 | 35 |
| 93 | 517 | 228 | 37 |
| 204 | 490 | 214 | 38 |
| 316 | 483 | 207 | 39 |
| 427 | 476 | 200 | 40 |
| 538 | 434 | 193 | 42 |
Monel 400 is renowned for its exceptional corrosion resistance in a wide variety of environments, particularly in seawater and reducing acid conditions. The alloy's high copper content provides excellent resistance to sulfuric acid and hydrofluoric acid, while the high nickel content provides resistance to alkaline environments.
The exceptional corrosion resistance of Monel 400 in seawater and reducing acids makes it the material of choice for numerous critical applications:
Hangbo Alloy Group manufactures and supplies Monel 400 in the following product forms, conforming to ASTM and ASME specifications:
| Standard | Description |
|---|---|
| ASTM B127 | Plate, Sheet, and Strip |
| ASTM B164 | Bar and Rod |
| ASTM B165 | Seamless Pipe and Tube |
| ASTM B163 | Condenser and Heat-Exchanger Tube |
| ASTM B564 | Forgings |
| ASTM B366 | Fittings |
| AWS A5.14 | Welding Wire (ERNiCu-7) |
| ASME SB-127 | Boiler and Pressure Vessel Code |
| ASME SB-165 | Boiler and Pressure Vessel Code |
UNS N04400 / W.Nr. 2.4360: 63% min nickel with 28-34% copper, up to 2.5% iron and small manganese, carbon and silicon limits.
Excellent seawater and hydrofluoric acid resistance, good strength and fabricability, and useful mechanical properties from cryogenic temperatures to about 480 °C.
Tensile about 550 MPa (80 ksi), yield about 240 MPa (35 ksi) and 35% elongation in the annealed condition.
About 480 °C (900 °F) for continuous service.
ASTM B164 (rod and bar) and B165 (seamless pipe and tube), plus UNS N04400 / W.Nr. 2.4360.
Marine hardware, seawater piping, pumps and valves, hydrofluoric acid alkylation, and chemical processing equipment.
Yes - with matching ERNiCu-7 (Monel 60) filler using GTAW or GMAW.
Round bar, plate, sheet, tube, pipe, forgings, wire and fittings, with mill test certification.
It resists seawater and reducing acids far better than most stainless grades and keeps toughness at sub-zero temperatures.
Hangbo Alloy Group maintains extensive inventory of Monel 400 in all standard product forms. We provide mill test certificates, third-party inspection reports (SGS, TUV), and custom processing services including cutting, machining, and surface finishing.
For quotations, material certifications, or technical consultation, contact our sales team or call +86 166 2109 2936. We typically respond within 10 minutes.
Request a quotation for Monel 400 round bars, tubes, plates, or forgings. We stock standard sizes and accept custom orders.