Monel R-405 · UNS N04405
Monel R-405 (N04405): composition, properties, fittings and flanges
Monel R-405 (N04405) is Free-machining nickel-copper alloy. Monel R-405 is specified at Nickel 63.0 - 70.0, Copper Balance, Aluminium 0.50 max. Monel R-405 is Monel 400 with a controlled sulphur addition for chip breaking, specified whenever a Monel part has to run at high production rates on automatic screw machines. Minimum…
- UNS
- N04405
- W. Nr.
- -
- Density
- 8.80 g/cm³ (0.318 lb/in³)
- Key strength
- 517 MPa / 75 ksi
Identification and standards
| Short form | Monel R-405 · UNS N04405 |
|---|---|
| Classification | Free-machining nickel-copper alloy |
| UNS | N04405 |
| Werkstoff number | - |
| Material family | Monel Alloys |
Chemical composition
| Element | Composition (wt %) | Why it is there |
|---|---|---|
| Nickel (Ni) | 63.0 - 70.0 | Matrix |
| Copper (Cu) | Balance | Matrix |
| Iron (Fe) | 2.50 max | Residual |
| Manganese (Mn) | 2.00 max | Deoxidation |
| Carbon (C) | 0.30 max | - |
| Silicon (Si) | 0.50 max | - |
| Sulphur (S) | 0.025 - 0.060 | Chip breaking for free machining |
| Aluminium (Al) | 0.50 max | - |
Note Single figures are maximum limits unless shown as a range. Always confirm against the heat-specific EN 10204 3.1 certificate supplied with your order.
Mechanical properties
| Tensile strength, min (annealed) | 517 MPa / 75 ksi |
|---|---|
| 0.2 % yield strength, min | 241 MPa / 35 ksi |
| Elongation in 2 in, min | 35 % |
| Typical hardness, annealed | 125 - 175 HB |
| Machinability rating vs Monel 400 | Substantially better chip control |
Warning Values depend on product form, section thickness and heat treatment. Larger sections generally achieve lower strength than thin product; always design against the applicable code allowable stress rather than these figures.
Physical properties
| Density | 8.80 g/cm³ (0.318 lb/in³) |
|---|---|
| Melting range | 1300 - 1350 °C (2370 - 2460 °F) |
| Modulus of elasticity | 179 GPa (26.0 x 10⁶ psi) |
| Thermal conductivity at 20 °C | 21.8 W/m·K |
| Mean coefficient of thermal expansion, 20-100 °C | 13.9 µm/m·°C |
| Specific heat capacity | 427 J/kg·K |
Specifications by product form
| Forgings & flanges | Not normally forged - supplied as bar |
|---|---|
| Butt weld fittings | Not recommended - sulphur causes weld cracking |
| Seamless pipe & tube | To order |
| Plate / sheet / strip | Not normally supplied |
| Bar / rod | ASTM B164 (UNS N04405) |
| Welding consumables | Welding not recommended |
| UNS / EN / China | UNS N04405 |
Product forms available
Hangbo supplies this grade in the following forms. Sizes outside the listed range can often be produced to order.
- Forged flanges blanks and finished flanges to ASME B16.5, B16.47 Series A/B and B16.36
- Butt weld elbows, tees, reducers, caps and stub ends to ASME B16.9 and MSS SP-43
- Seamless pipe and tube to the applicable ASTM / ASME pipe specification
- Forged rings, discs and hubs machined to your drawing
Typical applications
- Screw machine parts, fittings and valve components
- High-volume pump shafts and fasteners
- Marine hardware machined at production rates
- Instrument bodies and small machined parts
Welding, forming and machining
- Welding
- Avoid fusion welding. The controlled sulphur that makes R-405 machinable causes hot cracking in welds; use Monel 400 for welded fabrication.
- Heat treatment
- Anneal at 760 - 925 °C. Not age-hardenable.
- Hot and cold forming
- Hot work in the range stated by the mill for this grade, then re-solution or re-age before final machining so that the delivered condition matches the certificate.
- Machining
- Machine with sharp carbide or high-speed steel tooling, positive rake, constant feed and ample coolant. Never dwell - the surface work-hardens quickly.
Buy Monel R-405 from Hangbo
Material is supplied with full heat-number traceability, solution annealing or ageing performed under calibrated furnace control, and an EN 10204 3.1 certificate covering chemical analysis, mechanical properties, heat treatment records and the agreed NDT scope. Positive material identification and third party inspection and test reports from SGS are available for critical service.