# UNS C68300 Antimony-Silicon Brass

C68300 brass is a brass formulated for primary forming into wrought products. Cited properties are appropriate for the M30 (as hot extruded) condition. The graph bars on the material properties cards below compare C68300 brass to: wrought brasses (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

100 *GPa* 15 *x 10 ^{6} psi*

Elongation at Break

15 *%*

Poisson's Ratio

0.31

Rockwell B Hardness

60

Shear Modulus

40 *GPa* 5.8 *x 10 ^{6} psi*

Shear Strength

260 *MPa* 38 *x 10 ^{3} psi*

Tensile Strength: Ultimate (UTS)

430 *MPa* 62 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

260 *MPa* 38 *x 10 ^{3} psi*

## Thermal Properties

Latent Heat of Fusion

180 *J/g*

Maximum Temperature: Mechanical

120 *°C* 250 *°F*

Melting Completion (Liquidus)

900 *°C* 1660 *°F*

Melting Onset (Solidus)

890 *°C* 1630 *°F*

Specific Heat Capacity

390 *J/kg-K* 0.093 *BTU/lb-°F*

Thermal Conductivity

120 *W/m-K* 68 *BTU/h-ft-°F*

Thermal Expansion

20 *µm/m-K*

## Otherwise Unclassified Properties

Base Metal Price

23 *% relative*

Density

8.0 *g/cm ^{3}* 500

*lb/ft*

^{3}Embodied Carbon

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

Embodied Energy

46 *MJ/kg* 20 *x 10 ^{3} BTU/lb*

Embodied Water

340 *L/kg* 41 *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

20 *points*

Strength to Weight: Axial

15 *points*

Strength to Weight: Bending

16 *points*

Thermal Diffusivity

38 *mm ^{2}/s*

Thermal Shock Resistance

14 *points*

## Alloy Composition

Among wrought copper alloys, the composition of C68300 brass is notable for including cadmium (Cd) and antimony (Sb). Cadmium is used to improve strength at elevated temperatures. Antimony is used to improve certain types of corrosion resistance.

Cu | 59 to 63 | |

Zn | 34.2 to 40.4 | |

Si | 0.3 to 1.0 | |

Sb | 0.3 to 1.0 | |

Sn | 0.050 to 0.2 | |

Pb | 0 to 0.090 | |

Cd | 0 to 0.010 | |

res. | 0 to 0.5 |

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