Monel 400 (UNS N04400)
Monel 400 (UNS N04400, W.Nr. 2.4360) is a nickel–copper alloy of roughly two-thirds nickel and one-third copper, single-phase across its whole composition range. It resists seawater, hydrofluoric acid, sulphuric acid and caustic alkalis, and holds its strength from sub-zero temperatures up to about 480 °C — which is why it is used for marine shafting, heat exchangers, HF alkylation plant and valve trim.
Key Properties
- Nickel–copper, with no chromium. Nickel 63% minimum and copper 28-34%; the absence of chromium is why it behaves differently from the Inconel and Hastelloy families, suiting reducing conditions rather than oxidising ones.
- Hydrofluoric acid and flowing seawater are the services it is most often specified for, along with caustic alkalis.
- Useful from sub-zero to about 480 °C, with no ductile-to-brittle transition on cooling.
- Not age-hardenable. Strength comes from cold work. Where more is needed Monel K-500 adds aluminium and titanium for exactly that, and Monel R-405 is the free-machining version of this same chemistry.
Applications
- Marine propeller and pump shafting, seawater piping and fittings
- Heat exchangers and condensers in brackish and salt water
- Hydrofluoric acid alkylation plant and HF handling equipment
- Valve trim, pump casings and fasteners for chemical service
Monel 400 is the nickel alloy most used in hydrofluoric acid and is nearly as resistant as Nickel 200 to caustic soda, yet nitric acid above 0.5% attacks it rapidly. Its limits in each acid and alkali, against the other grades, are in our acid and alkali service guide.
Available Forms
Specification Overview
| Supplier & Manufacturer | Aurico Alloys LLP |
|---|---|
| Grade | Monel 400 (UNS N04400, W.Nr. 2.4360/2.4361) |
| Standards | ASTM B164, ASME SB164, EN, DIN, NACE MR0175 |
| Forms Available | Sheet, plate, round bar, foil, wire, coil |
| Certification | Mill test certificates (EN 10204 3.1), RoHS and REACH compliant, full traceability |
| Price | INR 2,500 – 6,500 per kg. Indicative USD 29 – 76 per kg; quoted against grade, form, size and quantity. |
Equivalent Grades & Standards
| Property | Value |
|---|---|
| UNS number | N04400 |
| Werkstoff / EN number | 2.4360 / 2.4361 |
| Density | 8.80 g/cm3 |
| Melting range | 1300-1350 °C |
| Modulus of elasticity (tension) | 26.0 × 10³ ksi |
| Modulus of elasticity (compression) | 26.0 × 10³ ksi |
| Modulus of elasticity (torsion) | 9.5 × 10³ ksi |
| Poisson's ratio | 0.32 |
| Curie temperature | 21-49 °C |
Identifiers and physical constants for Monel 400. A dash means no such designation is published for this grade.
Specifications by Product Form
Monel 400 (N04400) is supplied to a different standard in each form. Quote the one that matches the product you are ordering.
| Product form | Specification |
|---|---|
| Plate, sheet and strip | ASTM B127 / AMS 4544 |
| Rod and bar | ASTM B164 / B564 |
| Wire | ASTM B164 / AMS 4730 / 4731 |
| Pipe and tube | ASTM B163 / B165 |
| Fittings | ASTM B366 |
Chemical composition, mechanical properties and size ranges differ by product form — see the individual form pages above for the figures that apply to what you are ordering.
Aurico Alloys LLP stocks Monel 400 across the forms above, with material test certificates (EN 10204 3.1) and export-ready packaging from Mumbai, India. Contact us for stock availability and pricing.