UNS C71640 Copper-Nickel
C71640 copper-nickel is a copper-nickel alloy formulated for primary forming into wrought products. It has a moderately high base cost and a moderately high embodied energy among wrought copper-nickels.
The properties of C71640 copper-nickel include two common variations. This page shows summary ranges across both of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare C71640 copper-nickel 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
140 GPa 20 x 106 psi
Poisson's Ratio
0.33
Shear Modulus
52 GPa 7.6 x 106 psi
Tensile Strength: Ultimate (UTS)
490 to 630 MPa 71 to 91 x 103 psi
Tensile Strength: Yield (Proof)
190 to 460 MPa 28 to 66 x 103 psi
Thermal Properties
Latent Heat of Fusion
240 J/g
Maximum Temperature: Mechanical
260 °C 500 °F
Melting Completion (Liquidus)
1180 °C 2160 °F
Melting Onset (Solidus)
1120 °C 2050 °F
Specific Heat Capacity
410 J/kg-K 0.1 BTU/lb-°F
Thermal Conductivity
29 W/m-K 17 BTU/h-ft-°F
Thermal Expansion
15 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
7.0 % IACS
Electrical Conductivity: Equal Weight (Specific)
7.1 % IACS
Otherwise Unclassified Properties
Base Metal Price
40 % relative
Density
8.9 g/cm3 550 lb/ft3
Embodied Carbon
5.0 kg CO2/kg material
Embodied Energy
73 MJ/kg 31 x 103 BTU/lb
Embodied Water
280 L/kg 33 gal/lb
Common Calculations
Resilience: Unit (Modulus of Resilience)
130 to 750 kJ/m3
Stiffness to Weight: Axial
8.7 points
Stiffness to Weight: Bending
20 points
Strength to Weight: Axial
15 to 20 points
Strength to Weight: Bending
16 to 18 points
Thermal Diffusivity
8.2 mm2/s
Thermal Shock Resistance
16 to 21 points
Alloy Composition
Among wrought copper alloys, the composition of C71640 copper-nickel is notable for containing a comparatively high amount of iron (Fe) and including manganese (Mn). Iron is used to increase strength inexpensively. Manganese is used to improve strength without a proportional reduction in ductility.
| Cu | 61.7 to 67.8 | |
| Ni | 29 to 32 | |
| Mn | 1.5 to 2.5 | |
| Fe | 1.7 to 2.3 | |
| Zn | 0 to 1.0 | |
| 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 B111: Standard Specification for Copper and Copper-Alloy Seamless Condenser Tubes and Ferrule Stock
ASM Specialty Handbook: Copper and Copper Alloys, J. R. Davis (editor), 2001