1/8-Hard ASTM B780 Silver-Copper-Nickel Alloy
1/8-hard ASTM B780 alloy is ASTM B780 alloy in the 1/8-hard temper. It has the second lowest strength and second highest ductility compared to the other variants of ASTM B780 alloy.
The graph bars on the material properties cards below compare 1/8-hard ASTM B780 alloy to: precious metal electrical contact alloys (top), all alloys in the same category (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
83 GPa 12 x 106 psi
Elongation at Break
5.6 %
Poisson's Ratio
0.36
Shear Modulus
30 GPa 4.4 x 106 psi
Shear Strength
230 MPa 33 x 103 psi
Tensile Strength: Ultimate (UTS)
390 MPa 57 x 103 psi
Thermal Properties
Latent Heat of Fusion
140 J/g
Melting Completion (Liquidus)
860 °C 1580 °F
Specific Heat Capacity
270 J/kg-K 0.065 BTU/lb-°F
Thermal Expansion
18 µm/m-K
Other Material Properties
Density
10 g/cm3 630 lb/ft3
Electrical Conductivity: Equal Volume
74 % IACS
Electrical Conductivity: Equal Weight (Specific)
66 % IACS
Common Calculations
Stiffness to Weight: Axial
4.5 points
Stiffness to Weight: Bending
14 points
Strength to Weight: Axial
11 points
Strength to Weight: Bending
12 points
Thermal Shock Resistance
19 points
Alloy Composition
| Ag | 74 to 76 | |
| Cu | 23.5 to 25.7 | |
| Ni | 0.35 to 0.65 | |
| Zn | 0 to 0.060 | |
| Fe | 0 to 0.050 | |
| Cd | 0 to 0.050 | |
| Pb | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Further Reading
ASTM B780: Standard Specification for 75% Silver, 24.5% Copper, 0.5% Nickel Electrical Contact Alloy