UNS C86300 Manganese Bronze
C86300 bronze is a bronze formulated for casting. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. C86300 is the UNS number for this material. Older literature may refer to this material as ASTM Alloy 8C or ASTM Alloy E.
It has a very low base cost among cast bronzes. In addition, it has a very high tensile strength and a fairly low thermal conductivity.
The graph bars on the material properties cards below compare C86300 bronze to: cast bronzes (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
250
Compressive (Crushing) Strength
430 MPa 62 x 103 psi
Elastic (Young's, Tensile) Modulus
110 GPa 16 x 106 psi
Elongation at Break
14 %
Poisson's Ratio
0.32
Shear Modulus
42 GPa 6.1 x 106 psi
Tensile Strength: Ultimate (UTS)
850 MPa 120 x 103 psi
Tensile Strength: Yield (Proof)
480 MPa 69 x 103 psi
Thermal Properties
Latent Heat of Fusion
200 J/g
Maximum Temperature: Mechanical
160 °C 330 °F
Melting Completion (Liquidus)
920 °C 1690 °F
Melting Onset (Solidus)
890 °C 1630 °F
Specific Heat Capacity
420 J/kg-K 0.1 BTU/lb-°F
Thermal Conductivity
35 W/m-K 20 BTU/h-ft-°F
Thermal Expansion
20 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
8.0 % IACS
Electrical Conductivity: Equal Weight (Specific)
9.2 % IACS
Otherwise Unclassified Properties
Base Metal Price
23 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
3.0 kg CO2/kg material
Embodied Energy
51 MJ/kg 22 x 103 BTU/lb
Embodied Water
360 L/kg 43 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
100 MJ/m3
Resilience: Unit (Modulus of Resilience)
1030 kJ/m3
Stiffness to Weight: Axial
7.8 points
Stiffness to Weight: Bending
20 points
Strength to Weight: Axial
30 points
Strength to Weight: Bending
25 points
Thermal Diffusivity
11 mm2/s
Thermal Shock Resistance
28 points
Alloy Composition
Among cast copper alloys, the composition of C86300 bronze is notable for containing comparatively high amounts of iron (Fe) and aluminum (Al). Iron is used to increase strength inexpensively. Aluminum is used to add strength and oxidation resistance, at the cost of requiring additional care during casting.
| Cu | 60 to 66 | |
| Zn | 22 to 28 | |
| Al | 5.0 to 7.5 | |
| Mn | 2.5 to 5.0 | |
| Fe | 2.0 to 4.0 | |
| Ni | 0 to 1.0 | |
| Sn | 0 to 0.2 | |
| Pb | 0 to 0.2 | |
| res. | 0 to 1.0 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM B22: Standard Specification for Bronze Castings for Bridges and Turntables
ASTM B271: Standard Specification for Copper-Base Alloy Centrifugal Castings
ASTM B505: Standard Specification for Copper Alloy Continuous Castings
ASM Specialty Handbook: Copper and Copper Alloys, J. R. Davis (editor), 2001