UNS C77000 (CW410J) Nickel Silver
C77000 nickel silver is a copper-nickel alloy formulated for primary forming into wrought products. CW410J is the EN numeric designation for this material. C77000 is the UNS number. Additionally, the EN chemical designation is CuNi18Zn27. The British Standard (BS) designation is NS107. And the common industry name is 55-18 Nickel Silver. Older literature may refer to this material as ASTM Nickel Silver 4, but this is now discouraged.
It has a moderately low electrical conductivity among the wrought copper-nickels in the database.
The properties of C77000 nickel silver include seven common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare C77000 nickel silver to: wrought copper-nickels (top), all copper alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
120 GPa 17 x 106 psi
Poisson's Ratio
0.31
Rockwell B Hardness
52 to 99
Rockwell Superficial 30T Hardness
49 to 90
Shear Modulus
46 GPa 6.7 x 106 psi
Tensile Strength: Ultimate (UTS)
420 to 800 MPa 60 to 120 x 103 psi
Thermal Properties
Latent Heat of Fusion
200 J/g
Maximum Temperature: Mechanical
180 °C 360 °F
Melting Completion (Liquidus)
1050 °C 1930 °F
Melting Onset (Solidus)
1000 °C 1840 °F
Specific Heat Capacity
400 J/kg-K 0.095 BTU/lb-°F
Thermal Conductivity
29 W/m-K 17 BTU/h-ft-°F
Thermal Expansion
17 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
5.5 % IACS
Electrical Conductivity: Equal Weight (Specific)
6.0 % IACS
Otherwise Unclassified Properties
Base Metal Price
31 % relative
Density
8.3 g/cm3 520 lb/ft3
Embodied Carbon
4.1 kg CO2/kg material
Embodied Energy
63 MJ/kg 27 x 103 BTU/lb
Embodied Water
300 L/kg 36 gal/lb
Common Calculations
Stiffness to Weight: Axial
8.1 points
Stiffness to Weight: Bending
20 points
Strength to Weight: Axial
14 to 27 points
Strength to Weight: Bending
15 to 23 points
Thermal Diffusivity
8.8 mm2/s
Thermal Shock Resistance
15 to 28 points
Alloy Composition
Among wrought copper alloys, the composition of C77000 nickel silver is notable for including manganese (Mn) and nickel (Ni). Manganese is used to improve strength without a proportional reduction in ductility. Nickel is used to improve strength (particularly at elevated temperatures) and corrosion resistance.
| Cu | 53.5 to 56.5 | |
| Zn | 22.7 to 30 | |
| Ni | 16.5 to 19.5 | |
| Mn | 0 to 0.5 | |
| Fe | 0 to 0.25 | |
| Pb | 0 to 0.050 | |
| res. | 0 to 0.5 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM B151: Standard Specification for Copper-Nickel-Zinc Alloy (Nickel Silver) and Copper-Nickel Rod and Bar
ASTM B122: Standard Specification for Copper-Nickel-Tin Alloy, Copper-Nickel-Zinc Alloy (Nickel Silver), and Copper-Nickel Alloy Plate, Sheet, Strip, and Rolled Bar
Copper: Its Trade, Manufacture, Use, and Environmental Status, Gunter Joseph, 2001
Properties and Selection: Nonferrous Alloys and Special-Purpose Materials, ASM Handbook vol. 2, ASM International, 1993