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UNS C82700 Beryllium-Nickel Copper

C82700 copper is a lightly alloyed grade of copper, formulated for casting. Cited properties are appropriate for the heat treated (HT) condition. It has a very low melting temperature among cast coppers. In addition, it has the highest tensile strength and a fairly low thermal conductivity.

The graph bars on the material properties cards below compare C82700 copper to: cast coppers (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

120 GPa 18 x 106 psi

Elongation at Break

1.8 %

Poisson's Ratio


Rockwell C Hardness


Shear Modulus

46 GPa 6.7 x 106 psi

Tensile Strength: Ultimate (UTS)

1200 MPa 170 x 103 psi

Tensile Strength: Yield (Proof)

1020 MPa 150 x 103 psi

Thermal Properties

Latent Heat of Fusion

240 J/g

Maximum Temperature: Mechanical

300 °C 570 °F

Melting Completion (Liquidus)

950 °C 1750 °F

Melting Onset (Solidus)

860 °C 1570 °F

Specific Heat Capacity

380 J/kg-K 0.092 BTU/lb-°F

Thermal Conductivity

130 W/m-K 75 BTU/h-ft-°F

Thermal Expansion

17 µm/m-K

Electrical Properties

Electrical Conductivity: Equal Volume

20 % IACS

Electrical Conductivity: Equal Weight (Specific)

21 % IACS

Otherwise Unclassified Properties


8.7 g/cm3 550 lb/ft3

Embodied Carbon

12 kg CO2/kg material

Embodied Energy

180 MJ/kg 78 x 103 BTU/lb

Embodied Water

310 L/kg 37 gal/lb

Common Calculations

Resilience: Ultimate (Unit Rupture Work)

21 MJ/m3

Resilience: Unit (Modulus of Resilience)

4260 kJ/m3

Stiffness to Weight: Axial

7.8 points

Stiffness to Weight: Bending

19 points

Strength to Weight: Axial

38 points

Strength to Weight: Bending

29 points

Thermal Diffusivity

39 mm2/s

Thermal Shock Resistance

41 points

Alloy Composition

Among cast copper alloys, the composition of C82700 copper is notable for including beryllium (Be) and chromium (Cr). Beryllium is used to permit precipitation hardening (which increases strength) without much effect on electrical conductivity, but at the cost of substantial toxicity. Chromium additions permits certain types of heat treatment to improve mechanical strength.

Copper (Cu)Cu 94.6 to 96.7
Beryllium (Be)Be 2.4 to 2.6
Nickel (Ni)Ni 1.0 to 1.5
Iron (Fe)Fe 0 to 0.25
Silicon (Si)Si 0 to 0.15
Aluminum (Al)Al 0 to 0.15
Tin (Sn)Sn 0 to 0.1
Zinc (Zn)Zn 0 to 0.1
Chromium (Cr)Cr 0 to 0.090
Lead (Pb)Pb 0 to 0.020
Residualsres. 0 to 0.5

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

Followup Questions

Similar Alloys

Further Reading

ASM Specialty Handbook: Copper and Copper Alloys, J. R. Davis (editor), 2001