# UNS C81500 Chromium Copper

C81500 copper is a lightly alloyed grade of copper, formulated for casting. Cited properties are appropriate for the heat treated (HT) condition. It has the highest melting temperature among cast coppers. In addition, it has a very high ductility and a moderately high tensile strength.

The graph bars on the material properties cards below compare C81500 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

Brinell Hardness

110

Elastic (Young's, Tensile) Modulus

120 *GPa* 17 *x 10 ^{6} psi*

Elongation at Break

17 *%*

Poisson's Ratio

0.34

Shear Modulus

44 *GPa* 6.3 *x 10 ^{6} psi*

Tensile Strength: Ultimate (UTS)

350 *MPa* 51 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

280 *MPa* 40 *x 10 ^{3} psi*

## Thermal Properties

Latent Heat of Fusion

210 *J/g*

Maximum Temperature: Mechanical

200 *°C* 390 *°F*

Melting Completion (Liquidus)

1090 *°C* 1990 *°F*

Melting Onset (Solidus)

1080 *°C* 1970 *°F*

Specific Heat Capacity

390 *J/kg-K* 0.092 *BTU/lb-°F*

Thermal Conductivity

320 *W/m-K* 180 *BTU/h-ft-°F*

Thermal Expansion

17 *µm/m-K*

## Electrical Properties

Electrical Conductivity: Equal Volume

82 *% IACS*

Electrical Conductivity: Equal Weight (Specific)

83 *% IACS*

## Otherwise Unclassified Properties

Base Metal Price

31 *% relative*

Density

8.9 *g/cm ^{3}* 560

*lb/ft*

^{3}Embodied Carbon

2.6 *kg CO _{2}/kg material*

Embodied Energy

41 *MJ/kg* 18 *x 10 ^{3} BTU/lb*

Embodied Water

310 *L/kg* 37 *gal/lb*

## Common Calculations

Resilience: Ultimate (Unit Rupture Work)

56 *MJ/m ^{3}*

Resilience: Unit (Modulus of Resilience)

330 *kJ/m ^{3}*

Stiffness to Weight: Axial

7.3 *points*

Stiffness to Weight: Bending

18 *points*

Strength to Weight: Axial

11 *points*

Strength to Weight: Bending

12 *points*

Thermal Diffusivity

91 *mm ^{2}/s*

Thermal Shock Resistance

12 *points*

## Alloy Composition

Among cast copper alloys, the composition of C81500 copper is notable for including chromium (Cr). Chromium additions permits certain types of heat treatment to improve mechanical strength.

Cu | 97.4 to 99.6 | |

Cr | 0.4 to 1.5 | |

Si | 0 to 0.15 | |

Fe | 0 to 0.1 | |

Al | 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