Monel R-405 (UNS N04405)
Monel R-405 (UNS N04405) is Monel 400 with sulphur deliberately added — 0.025 to 0.060%, stated as a minimum rather than a ceiling. The sulphide inclusions break the chip, and that is the whole point of the grade: it is bought to be screw-machined at rates plain Monel 400 will not sustain. Every other element matches 400, so the seawater, hydrofluoric acid and caustic resistance comes with it unchanged.
Key Properties
- Free-machining by design. Sulphur 0.025-0.060% is the only difference from Monel 400, and it is specified as a minimum because the inclusions are wanted.
- Monel 400's chemistry otherwise — nickel 63% minimum, copper 28-34% — so corrosion behaviour follows the parent grade.
- Bar and wire only. Special Metals publishes ASTM B164 for rod, bar and wire and no flat-product standard: added sulphur has no purpose in plate or sheet, and would only harm hot workability.
- Monel 400 is the alternative wherever the part is welded rather than machined — sulphur is what makes R-405 the poorer choice for welding.
Applications
- Valve stems and seats machined in volume
- Fasteners, studs and screw-machined fittings
- Meter, instrument and pump components
- Marine and chemical hardware where Monel 400 corrosion resistance is needed on a turned part
Available Forms
Equivalent Grades & Standards
| Property | Value |
|---|---|
| UNS number | N04405 |
| Werkstoff / EN number | — |
| 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 405. A dash means no such designation is published for this grade.
Specifications by Product Form
Monel 405 (N04405) is supplied to a different standard in each form. Quote the one that matches the product you are ordering.
| Product form | Specification |
|---|---|
| Rod and bar | ASTM B164 |
| Wire | ASTM B164 |
Aurico Alloys LLP supplies Monel Alloy 405 across all 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.