Hidurel® 5
Also known as UNS C64700, EN CW111C
Hidurel® 5 is a high-strength copper-silicon-nickel alloy combining seawater corrosion resistance with good machinability.
Hidurel® 5 (UNS C64700) is a Copper-Silicon-Nickel alloy developed by Langley Alloys, combining the inherent seawater corrosion resistance and biofouling resistance of copper alloys with high strength achieved through silicon and nickel additions. Machinability is excellent.
Its resistance to seawater corrosion, erosion-corrosion and cavitation, combined with high strength, makes it well suited to propeller shafts, valve stems, marine fasteners and other structural components exposed to seawater service.
We stock bar in the UK and USA. Plate, tube and fittings are available on enquiry; forgings and castings to order.
- Excellent seawater corrosion resistance and biofouling resistance
- High strength compared to standard Cu-Ni alloys
- Good resistance to erosion-corrosion and cavitation
- Excellent machinability
| Element | Min | Max |
|---|---|---|
| Copper (Cu) | Bal | |
| Nickel (Ni) | 2.30 | 3.50 |
| Silicon (Si) | 0.40 | 0.80 |
| Iron (Fe) | - | 0.10 |
| Manganese (Mn) | 0.05 | 0.30 |
| Aluminium (Al) | - | 0.02 |
| Property | Imperial | Metric |
|---|---|---|
| 0.1% Proof stress (min) | 60.5 ksi | 417 N/mm² |
| 0.2% Proof stress (min) | 62.4 ksi | 430 N/mm² |
| Tensile strength (min) | 85.1 ksi | 587 N/mm² |
| Elongation (5.65√S0 & 4D) | 18% | |
| Hardness (Brinell) | 159-207 | |
| Impact strength (Charpy) | 27 J min |
| Property | Imperial | Metric |
|---|---|---|
| 0.1% Proof stress (min) | 60.5 ksi | 417 N/mm² |
| Tensile strength (min) | 85.1 ksi | 587 N/mm² |
| Elongation (5.65√S0 & 4D) | 15% | |
| Hardness (Brinell) | 159-207 | |
| Impact strength (Charpy) | 27 J min |
| Property | Value |
|---|---|
| Density (kg/m³) | 8870 |
| Young's modulus (kN/mm²) | 284 |
| Modulus of rigidity (kN/mm²) | 106 |
| Poisson's ratio | 0.39 |
| Specific electrical resistance, 20°C (µΩ.m) | 0.043 |
| Electrical conductivity, 20°C (% IACS) | 6.9 / (40% IACS) |
| Mean coefficient of thermal expansion, 20-400°C (m/m/°C) | 16 x 10⁻⁶ |
| Specific heat, 20°C (J/kg.K) | 419 |
| Thermal conductivity, 20°C (W/m.K) | 190 |
| Thermal conductivity, 200°C (W/m.K) | 211 |
| Thermal conductivity, 400°C (W/m.K) | 232 |
Equivalents & cross-references
Standard designations
- UNS
- C64700Unified Numbering System for copper alloys
- EN
- CW111CEuropean designation; CuNi2Si
- ASTM
- B411 C64700Rod, bar and shapes
- BS
- 4577British Standard Type A3/2 2B25 / B25Aerospace specification
- DTD
- 498UK Defence Technology Directorate specification
- MSRR
- 8501Rolls-Royce material specification
- W.Nr.
- 2.0855German material number
Hidurel® 5 is also designated UNS C64700, EN CW111C, ASTM B411 C64700, BS 4577, BS 2B25 / B25, DTD 498, MSRR 8501 and W.Nr. 2.0855.
Common questions
What is the UNS number for Hidurel 5?
Hidurel 5 is a precipitation-hardening copper-nickel-silicon alloy covered by UNS C64700 (CuNi2Si), ASTM B411 C64700, BS4577, BS 2B25/B25, DTD 498, MSRR 8501, CW111C and DIN 2.0855. It combines high electrical and thermal conductivity with very good notch ductility and high mechanical strength, and meets DTD 498, BS 4577 Type A3/2 and Rolls Royce MSRR 8501. Langley Alloys stocks it as bar; plate, tube and fittings are available on enquiry, and forgings and castings are to order.
What is Hidurel 5 used for?
Hidurel 5 is used for naval applications including ship and submarine shafts and bolting, flanges, swash plate pump components and mine detection equipment; automotive valve guides, seats and bushes; resistance welding electrodes; plastic moulding and forging dies; aerospace engine bearing cages and undercarriage components; and thrust pads, mechanical seals and bushes in subsea valves. Its excellent bearing and anti-friction properties are particularly good when operating against hardened steel.
Does Hidurel 5 offer high conductivity and corrosion resistance?
Yes. Hidurel 5 combines high mechanical strength with good electrical conductivity of 40% IACS and thermal conductivity of 190 W/m.K at 20°C. It has excellent corrosion resistance in marine and industrial conditions, is resistant to hydrogen embrittlement, and is essentially non-magnetic with a permeability below 1.001. It also shows no loss of impact strength down to -196°C.
What is UNS C64700?
UNS C64700 is the Unified Numbering System designation for a copper-nickel-silicon alloy (CuNi2Si / CW111C). Langley Alloys stocks this alloy as Hidurel® 5 to ASTM B411, BS 4577 Type A3/2, DTD 498, and Rolls-Royce MSRR 8501.
What is MSRR 8501?
MSRR 8501 is the Rolls-Royce material specification for the copper-nickel-silicon alloy UNS C64700 (CuNi2Si), stocked by Langley Alloys as Hidurel® 5. The grade also meets BS 4577 Type A3/2, DTD 498, ASTM B411, and DIN 2.0855.
What is the density of Hidurel 5?
Hidurel 5 has a density of approximately 8.87 g/cm³ (8870 kg/m³).
Is Hidurel 5 magnetic?
No. As a copper-base alloy, Hidurel 5 is non-magnetic.
Datasheets
Hidurel® 5 is supplied solution treated and age-hardened; each bar is ultrasonically tested and visually inspected.
Request a quote
Tell us the grade, form and sizes.
Fast quotes from UK and US stock - bar, plate and pipe, cut and certified to spec.