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ASTM B540 Palladium Electrical Contact Alloy

ASTM B540 palladium is a precious metal alloy formulated for use in electrical contacts. It can have the highest tensile strength and a moderately low electrical conductivity among precious metal electrical contact alloys.

The properties of ASTM B540 palladium 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 B540 palladium 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

110 GPa 16 x 106 psi

Elongation at Break

1.1 to 14 %

Fatigue Strength

350 MPa 50 x 103 psi

Knoop Hardness

230 to 380

Poisson's Ratio


Shear Modulus

39 GPa 5.6 x 106 psi

Shear Strength

500 to 700 MPa 73 to 100 x 103 psi

Tensile Strength: Ultimate (UTS)

830 to 1240 MPa 120 to 180 x 103 psi

Tensile Strength: Yield (Proof)

620 to 1000 MPa 90 to 150 x 103 psi

Thermal Properties

Latent Heat of Fusion

140 J/g

Melting Completion (Liquidus)

1220 °C 2220 °F

Melting Onset (Solidus)

1020 °C 1860 °F

Specific Heat Capacity

240 J/kg-K 0.057 BTU/lb-°F

Thermal Expansion

14 µm/m-K

Other Material Properties


13 g/cm3 790 lb/ft3

Electrical Conductivity: Equal Volume

4.9 to 5.5 % IACS

Electrical Conductivity: Equal Weight (Specific)

3.5 to 3.9 % IACS

Common Calculations

Resilience: Ultimate (Unit Rupture Work)

13 to 100 MJ/m3

Resilience: Unit (Modulus of Resilience)

1790 to 4660 kJ/m3

Stiffness to Weight: Axial

4.7 points

Stiffness to Weight: Bending

12 points

Strength to Weight: Axial

18 to 27 points

Strength to Weight: Bending

15 to 20 points

Thermal Shock Resistance

41 to 61 points

Alloy Composition

Palladium (Pd)Pd 34 to 36
Silver (Ag)Ag 29 to 31
Copper (Cu)Cu 13.5 to 14.5
Gold (Au)Au 9.5 to 10.5
Platinum (Pt)Pt 9.5 to 10.5
Zinc (Zn)Zn 0.8 to 1.2
Residualsres. 0 to 0.3

All values are % weight. Ranges represent what is permitted under applicable standards.

Followup Questions

Similar Alloys

Further Reading

ASTM B540: Standard Specification for Palladium Electrical Contact Alloy