UNS C77400 Nickel Silver
C77400 nickel silver is a copper-nickel alloy formulated for primary forming into wrought products. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. C77400 is the UNS number for this material. Additionally, the common industry name is 45-10 Nickel Silver.
It has a moderately low base cost among wrought copper-nickels. In addition, it has the lowest melting temperature and a moderately high tensile strength.
The graph bars on the material properties cards below compare C77400 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
110 GPa 16 x 106 psi
Elongation at Break
25 %
Poisson's Ratio
0.3
Rockwell B Hardness
73
Shear Modulus
42 GPa 6.1 x 106 psi
Shear Strength
360 MPa 53 x 103 psi
Tensile Strength: Ultimate (UTS)
570 MPa 83 x 103 psi
Tensile Strength: Yield (Proof)
250 MPa 36 x 103 psi
Thermal Properties
Latent Heat of Fusion
170 J/g
Maximum Temperature: Mechanical
130 °C 260 °F
Melting Completion (Liquidus)
810 °C 1490 °F
Melting Onset (Solidus)
770 °C 1420 °F
Specific Heat Capacity
390 J/kg-K 0.094 BTU/lb-°F
Thermal Expansion
21 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
27 % IACS
Electrical Conductivity: Equal Weight (Specific)
31 % IACS
Otherwise Unclassified Properties
Base Metal Price
25 % relative
Density
7.9 g/cm3 490 lb/ft3
Embodied Carbon
3.5 kg CO2/kg material
Embodied Energy
57 MJ/kg 24 x 103 BTU/lb
Embodied Water
320 L/kg 38 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
120 MJ/m3
Resilience: Unit (Modulus of Resilience)
290 kJ/m3
Stiffness to Weight: Axial
7.7 points
Stiffness to Weight: Bending
20 points
Strength to Weight: Axial
20 points
Strength to Weight: Bending
19 points
Thermal Shock Resistance
18 points
Alloy Composition
Among wrought copper alloys, the composition of C77400 nickel silver is notable for including nickel (Ni). Nickel is used to improve strength (particularly at elevated temperatures) and corrosion resistance.
| Cu | 43 to 47 | |
| Zn | 41.3 to 48 | |
| Ni | 9.0 to 11 | |
| Pb | 0 to 0.2 | |
| res. | 0 to 0.5 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM B124: Standard Specification for Copper and Copper Alloy Forging Rod, Bar, and Shapes
ASTM B283: Standard Specification for Copper and Copper-Alloy Die Forgings (Hot-Pressed)
ASM Specialty Handbook: Copper and Copper Alloys, J. R. Davis (editor), 2001