UNS C24000 (CW503L) Low Brass
C24000 brass is a brass formulated for primary forming into wrought products. CW503L is the EN numeric designation for this material. C24000 is the UNS number. Additionally, the EN chemical designation is CuZn20. The British Standard (BS) designation is CZ103. And the common industry name is 80-20 Low Brass.
It has a moderately high thermal conductivity among the wrought brasses in the database.
The properties of C24000 brass include nine common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare C24000 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
110 GPa 16 x 106 psi
Poisson's Ratio
0.32
Rockwell B Hardness
52 to 91
Rockwell Superficial 30T Hardness
51 to 78
Shear Modulus
42 GPa 6.0 x 106 psi
Tensile Strength: Ultimate (UTS)
310 to 640 MPa 44 to 93 x 103 psi
Thermal Properties
Latent Heat of Fusion
190 J/g
Maximum Temperature: Mechanical
160 °C 320 °F
Melting Completion (Liquidus)
1000 °C 1830 °F
Melting Onset (Solidus)
970 °C 1770 °F
Solidification (Pattern Maker's) Shrinkage
5.5 %
Specific Heat Capacity
390 J/kg-K 0.092 BTU/lb-°F
Thermal Conductivity
140 W/m-K 81 BTU/h-ft-°F
Thermal Expansion
19 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
32 % IACS
Electrical Conductivity: Equal Weight (Specific)
34 % IACS
Otherwise Unclassified Properties
Base Metal Price
27 % relative
Density
8.5 g/cm3 530 lb/ft3
Embodied Carbon
2.6 kg CO2/kg material
Embodied Energy
43 MJ/kg 19 x 103 BTU/lb
Embodied Water
320 L/kg 38 gal/lb
Common Calculations
Stiffness to Weight: Axial
7.2 points
Stiffness to Weight: Bending
19 points
Strength to Weight: Axial
10 to 21 points
Strength to Weight: Bending
12 to 20 points
Thermal Diffusivity
43 mm2/s
Thermal Shock Resistance
10 to 22 points
Alloy Composition
Among wrought copper alloys, the composition of C24000 brass is notable for containing comparatively high amounts of iron (Fe) and lead (Pb). Iron is used to increase strength inexpensively. Lead is used to improve machinability and bearing properties, at the cost of toxicity.
| Cu | 78.5 to 81.5 | |
| Zn | 18.2 to 21.5 | |
| Fe | 0 to 0.050 | |
| Pb | 0 to 0.050 | |
| res. | 0 to 0.2 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM B134: Standard Specification for Brass Wire
ASTM B36: Standard Specification for Brass Plate, Sheet, Strip, And Rolled Bar
Copper: Its Trade, Manufacture, Use, and Environmental Status, Gunter Joseph, 2001
Properties and Selection: Nonferrous Alloys and Special-Purpose Materials, ASM Handbook vol. 2, ASM International, 1993