UNS C87900 Silicon Brass
C87900 brass is a brass formulated for casting. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition.
It has a moderately high thermal conductivity among cast brasses. In addition, it has a fairly low electrical conductivity and a moderately high tensile strength.
The graph bars on the material properties cards below compare C87900 brass to: cast 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
110 GPa 15 x 106 psi
Elongation at Break
25 %
Poisson's Ratio
0.31
Rockwell B Hardness
70
Shear Modulus
41 GPa 5.9 x 106 psi
Tensile Strength: Ultimate (UTS)
480 MPa 70 x 103 psi
Tensile Strength: Yield (Proof)
240 MPa 35 x 103 psi
Thermal Properties
Latent Heat of Fusion
190 J/g
Maximum Temperature: Mechanical
130 °C 270 °F
Melting Completion (Liquidus)
930 °C 1700 °F
Melting Onset (Solidus)
900 °C 1650 °F
Specific Heat Capacity
390 J/kg-K 0.094 BTU/lb-°F
Thermal Conductivity
120 W/m-K 67 BTU/h-ft-°F
Thermal Expansion
20 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
15 % IACS
Electrical Conductivity: Equal Weight (Specific)
17 % IACS
Otherwise Unclassified Properties
Base Metal Price
24 % relative
Density
8.1 g/cm3 500 lb/ft3
Embodied Carbon
2.7 kg CO2/kg material
Embodied Energy
46 MJ/kg 20 x 103 BTU/lb
Embodied Water
320 L/kg 38 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
100 MJ/m3
Resilience: Unit (Modulus of Resilience)
270 kJ/m3
Stiffness to Weight: Axial
7.3 points
Stiffness to Weight: Bending
20 points
Strength to Weight: Axial
17 points
Strength to Weight: Bending
17 points
Thermal Diffusivity
37 mm2/s
Thermal Shock Resistance
16 points
Alloy Composition
Among cast copper alloys, the composition of C87900 brass is notable for including arsenic (As). Arsenic is used to protect the alloy against dezincification.
| Cu | 63 to 69.2 | |
| Zn | 30 to 36 | |
| Si | 0.8 to 1.2 | |
| Ni | 0 to 0.5 | |
| Fe | 0 to 0.4 | |
| Sn | 0 to 0.25 | |
| Pb | 0 to 0.25 | |
| Mn | 0 to 0.15 | |
| Al | 0 to 0.15 | |
| S | 0 to 0.050 | |
| Sb | 0 to 0.050 | |
| As | 0 to 0.050 | |
| P | 0 to 0.010 |
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