UNS C67300 Leaded Manganese Bronze
C67300 bronze is a brass formulated for primary forming into wrought products. Cited properties are appropriate for the H50 (extruded and drawn) temper.
It has a moderately low melting temperature among wrought brasses. In addition, it has a moderately low thermal conductivity and a moderately high tensile strength.
The graph bars on the material properties cards below compare C67300 bronze 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 15 x 106 psi
Elongation at Break
12 %
Poisson's Ratio
0.31
Rockwell B Hardness
91
Shear Modulus
41 GPa 5.9 x 106 psi
Shear Strength
300 MPa 44 x 103 psi
Tensile Strength: Ultimate (UTS)
500 MPa 73 x 103 psi
Tensile Strength: Yield (Proof)
340 MPa 50 x 103 psi
Thermal Properties
Latent Heat of Fusion
190 J/g
Maximum Temperature: Mechanical
130 °C 260 °F
Melting Completion (Liquidus)
870 °C 1610 °F
Melting Onset (Solidus)
830 °C 1530 °F
Specific Heat Capacity
390 J/kg-K 0.093 BTU/lb-°F
Thermal Conductivity
95 W/m-K 55 BTU/h-ft-°F
Thermal Expansion
20 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
22 % IACS
Electrical Conductivity: Equal Weight (Specific)
25 % IACS
Otherwise Unclassified Properties
Base Metal Price
23 % relative
Density
8.0 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)
55 MJ/m3
Resilience: Unit (Modulus of Resilience)
550 kJ/m3
Stiffness to Weight: Axial
7.4 points
Stiffness to Weight: Bending
20 points
Strength to Weight: Axial
17 points
Strength to Weight: Bending
17 points
Thermal Diffusivity
30 mm2/s
Thermal Shock Resistance
16 points
Alloy Composition
Among wrought copper alloys, the composition of C67300 bronze is notable for including aluminum (Al) and silicon (Si). Aluminum is used to add strength and oxidation resistance. Silicon is used to increase strength at the expense of ductility. It also lowers the melting temperature and raises the fluidity of the alloy.
| Cu | 58 to 63 | |
| Zn | 27.2 to 39.1 | |
| Mn | 2.0 to 3.5 | |
| Pb | 0.4 to 3.0 | |
| Si | 0.5 to 1.5 | |
| Fe | 0 to 0.5 | |
| Sn | 0 to 0.3 | |
| Ni | 0 to 0.25 | |
| Al | 0 to 0.25 | |
| res. | 0 to 0.5 |
All values are % weight. Ranges represent what is permitted under applicable standards.