UNS C97800 Leaded Nickel Silver
C97800 nickel silver is a copper-nickel alloy formulated for casting. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. C97800 is the UNS number for this material. Additionally, the common industry name is 25% Leaded Nickel Silver. Older literature may refer to this material as ASTM Alloy 11B, but this is now discouraged.
It has a fairly low electrical conductivity among cast copper-nickels. In addition, it has a moderately low thermal conductivity and a fairly high melting temperature.
The graph bars on the material properties cards below compare C97800 nickel silver to: cast 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
130 GPa 19 x 106 psi
Elongation at Break
10 %
Poisson's Ratio
0.33
Shear Modulus
48 GPa 7.0 x 106 psi
Tensile Strength: Ultimate (UTS)
370 MPa 54 x 103 psi
Tensile Strength: Yield (Proof)
170 MPa 25 x 103 psi
Thermal Properties
Latent Heat of Fusion
220 J/g
Maximum Temperature: Mechanical
230 °C 440 °F
Melting Completion (Liquidus)
1180 °C 2160 °F
Melting Onset (Solidus)
1140 °C 2080 °F
Specific Heat Capacity
390 J/kg-K 0.093 BTU/lb-°F
Thermal Conductivity
25 W/m-K 14 BTU/h-ft-°F
Thermal Expansion
16 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
4.0 % IACS
Electrical Conductivity: Equal Weight (Specific)
4.1 % IACS
Otherwise Unclassified Properties
Base Metal Price
40 % relative
Density
8.8 g/cm3 550 lb/ft3
Embodied Carbon
5.1 kg CO2/kg material
Embodied Energy
76 MJ/kg 33 x 103 BTU/lb
Embodied Water
330 L/kg 39 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
31 MJ/m3
Resilience: Unit (Modulus of Resilience)
120 kJ/m3
Stiffness to Weight: Axial
8.1 points
Stiffness to Weight: Bending
19 points
Strength to Weight: Axial
12 points
Strength to Weight: Bending
13 points
Thermal Diffusivity
7.3 mm2/s
Thermal Shock Resistance
13 points
Alloy Composition
Among cast copper alloys, the composition of C97800 nickel silver is notable for containing comparatively high amounts of nickel (Ni) and lead (Pb). Nickel is used to improve strength (particularly at elevated temperatures) and corrosion resistance. It also creates the need for additional care during casting. Lead is used to improve machinability and bearing properties, at the cost of toxicity. It also adds pressure tightness to castings.
| Cu | 64 to 67 | |
| Ni | 24 to 27 | |
| Sn | 4.0 to 5.5 | |
| Zn | 1.0 to 4.0 | |
| Pb | 1.0 to 2.5 | |
| Fe | 0 to 1.5 | |
| Sb | 0 to 0.2 | |
| Si | 0 to 0.15 | |
| S | 0 to 0.080 | |
| P | 0 to 0.050 | |
| Al | 0 to 0.0050 | |
| res. | 0 to 0.4 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM B271: Standard Specification for Copper-Base Alloy Centrifugal Castings
ASTM B505: Standard Specification for Copper Alloy Continuous Castings
Properties and Selection: Nonferrous Alloys and Special-Purpose Materials, ASM Handbook vol. 2, ASM International, 1993