ASTM B477 Gold-Nickel-Silver Electrical Contact Alloy
ASTM B477 Au-Ni-Ag is a precious metal alloy formulated for use in electrical contacts.
The properties of ASTM B477 Au-Ni-Ag include four 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 ASTM B477 Au-Ni-Ag 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
95 GPa 14 x 106 psi
Elongation at Break
5.5 to 11 %
Knoop Hardness
100 to 190
Poisson's Ratio
0.41
Shear Modulus
34 GPa 4.9 x 106 psi
Shear Strength
190 to 320 MPa 27 to 46 x 103 psi
Tensile Strength: Ultimate (UTS)
310 to 550 MPa 45 to 80 x 103 psi
Thermal Properties
Latent Heat of Fusion
80 J/g
Melting Completion (Liquidus)
1010 °C 1850 °F
Melting Onset (Solidus)
930 °C 1700 °F
Specific Heat Capacity
160 J/kg-K 0.039 BTU/lb-°F
Thermal Expansion
15 µm/m-K
Other Material Properties
Density
17 g/cm3 1060 lb/ft3
Electrical Conductivity: Equal Volume
14 % IACS
Electrical Conductivity: Equal Weight (Specific)
7.5 % IACS
Common Calculations
Stiffness to Weight: Axial
3.1 points
Stiffness to Weight: Bending
8.9 points
Strength to Weight: Axial
5.0 to 9.0 points
Strength to Weight: Bending
6.0 to 8.8 points
Thermal Shock Resistance
16 to 28 points
Alloy Composition
| Au | 74.2 to 75.8 | |
| Ag | 21.4 to 22.6 | |
| Ni | 2.6 to 3.4 | |
| res. | 0 to 0.3 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM B477: Standard Specification for Gold-Silver-Nickel Electrical Contact Alloy
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015