Monel 400 — Sheet, Plate, Coil, Pipe & Tube & Fittings
Also sold as Alloy 400 · UNS N04400 · W.Nr 2.4360 · Nicorros
Monel 400 is a nickel–copper alloy, chosen for seawater, hydrofluoric acid and marine service. We supply it as sheet, plate, coil, pipe & tube, fittings, flanges, fasteners, with EN 10204 3.1 certificates, from Mumbai to India, the Gulf, South-East Asia, South America, Europe, the UK and the USA.
- UNS N04400
- W.Nr 2.4360
- ρ 8.8 g/cm³
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
Monel 400 Specifications by Product (ASTM / ASME)
The material standard changes with the product form. This is the table buyers ask for most.
| Product | Material standard | Dimensions |
|---|---|---|
| Monel 400 sheet | ASTM B127 | ASTM A480 / B906 |
| Monel 400 plate | ASTM B127 | ASTM A480 / B906 / A20 |
| Monel 400 coil | ASTM B127 | ASTM A480 |
| Monel 400 pipe & tube | ASTM B165 · ASTM B725 | ASME B36.19 / B36.10 |
| Monel 400 fittings | ASTM B366 WPNC · ASTM B564 | ASME B16.9 · B16.11 |
| Monel 400 flanges | ASTM B564 | ASME B16.5 · B16.47 |
| Monel 400 fasteners | ASTM B164 | ASME B18.2.1 · B18.2.2 |
Monel 400 Chemical Composition
| Element | Weight % |
|---|---|
| Nickel (+Co) | 63.0 min |
| Copper | 28.0 – 34.0 |
| Iron | 2.5 max |
| Manganese | 2.0 max |
| Carbon | 0.3 max |
| Silicon | 0.5 max |
| Sulphur | 0.024 max |
Monel 400 Mechanical Properties
| Annealed plate | Value |
|---|---|
| Tensile strength | 480 MPa · 70 ksi |
| Yield strength 0.2% | 195 MPa · 28 ksi |
| Elongation | 35% |
Density & Physical Properties
| Property | Value |
|---|---|
| Density | 8.8 g/cm³ |
| Melting range | 1300 – 1350 °C |
| Magnetic | Slightly magnetic at room temperature |
Monel 400 Equivalent Grades
Values per ASTM B127 for UNS N04400. Confirm against the edition on your purchase order.
Monel 400 Corrosion Resistance — What Each Element Does
Very low corrosion rates in flowing seawater and brackish water.
One of the few alloys that handles hydrofluoric acid in all concentrations (air-free).
Resists caustic alkalis and chloride stress-corrosion cracking.
Avoid nitric acid, aerated ammonia and oxidising salts.
Monel 400 vs 625, 2507 and 316L
| Grade | PREN (approx.) | Pick it for |
|---|---|---|
| Monel 400 | — | Seawater, hydrofluoric acid and marine service |
| SS 316 / 316L | ≈ 24 | Chloride-bearing process fluids, marine air and pharmaceutical service |
| Super Duplex 2507 | ≈ 42 | Seawater and high-chloride service where strength also matters |
| Inconel 625 | ≈ 51 | Seawater, high strength and high temperature in one alloy |
Welding Monel 400
| Matching filler | ERNiCu-7 (AWS A5.14) |
|---|---|
| Also used | ENiCu-7 electrode |
Monel 400 — questions buyers ask
What is Monel 400?
Monel 400 is a nickel–copper alloy. It is chosen for seawater, hydrofluoric acid and marine service.
Which standards cover Monel 400 products?
Sheet: ASTM B127; Plate: ASTM B127; Coil: ASTM B127; Pipe & Tube: ASTM B165 · ASTM B725; Fittings: ASTM B366 WPNC · ASTM B564; Flanges: ASTM B564; Fasteners: ASTM B164. Always name the standard and edition on your order.
What is the UNS number of Monel 400?
UNS N04400, with the European material number W.Nr 2.4360.
What is the density of Monel 400?
8.8 g/cm³ — use it to calculate weights: plate kg = L(m) × W(m) × t(mm) × 8.8.
Monel 400 or SS 316 / 316L?
Monel 400 suits seawater, hydrofluoric acid and marine service; SS 316 / 316L is the step up for chloride-bearing process fluids, marine air and pharmaceutical service.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026