UNS C82600 (Alloy 245C) Beryllium Copper
C82600 copper is a lightly alloyed grade of copper, formulated for casting. C82600 is the UNS number for this material. Older literature may refer to this material as ASTM Alloy 245C or ASTM Alloy 245CT.
It has a very low melting temperature among cast coppers. In addition, it has a very low electrical conductivity and can have a very high tensile strength.
The properties of C82600 copper include two common variations. This page shows summary ranges across both of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare C82600 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
1.0 to 20 %
Poisson's Ratio
0.33
Shear Modulus
46 GPa 6.6 x 106 psi
Tensile Strength: Ultimate (UTS)
570 to 1140 MPa 82 to 170 x 103 psi
Tensile Strength: Yield (Proof)
320 to 1070 MPa 47 to 160 x 103 psi
Thermal Properties
Latent Heat of Fusion
240 J/g
Maximum Temperature: Mechanical
300 °C 560 °F
Melting Completion (Liquidus)
950 °C 1750 °F
Melting Onset (Solidus)
860 °C 1570 °F
Specific Heat Capacity
390 J/kg-K 0.092 BTU/lb-°F
Thermal Conductivity
130 W/m-K 73 BTU/h-ft-°F
Thermal Expansion
17 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
19 % IACS
Electrical Conductivity: Equal Weight (Specific)
20 % IACS
Otherwise Unclassified Properties
Density
8.7 g/cm3 540 lb/ft3
Embodied Carbon
11 kg CO2/kg material
Embodied Energy
180 MJ/kg 76 x 103 BTU/lb
Embodied Water
310 L/kg 37 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
11 to 97 MJ/m3
Resilience: Unit (Modulus of Resilience)
430 to 4690 kJ/m3
Stiffness to Weight: Axial
7.8 points
Stiffness to Weight: Bending
19 points
Strength to Weight: Axial
18 to 36 points
Strength to Weight: Bending
17 to 28 points
Thermal Diffusivity
37 mm2/s
Thermal Shock Resistance
19 to 39 points
Alloy Composition
Among cast copper alloys, the composition of C82600 copper is notable for including cobalt (Co) and beryllium (Be). Cobalt is used to improve strength. Beryllium is used to permit precipitation hardening (which increases strength) without much effect on electrical conductivity, but at the cost of substantial toxicity.
| Cu | 94.9 to 97.2 | |
| Be | 2.3 to 2.6 | |
| Co | 0.35 to 0.65 | |
| Si | 0.2 to 0.35 | |
| Fe | 0 to 0.25 | |
| Ni | 0 to 0.2 | |
| Al | 0 to 0.15 | |
| Ti | 0 to 0.12 | |
| Cr | 0 to 0.1 | |
| Sn | 0 to 0.1 | |
| Zn | 0 to 0.1 | |
| Pb | 0 to 0.020 | |
| res. | 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
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015