UNS C86200 Manganese Bronze
C86200 bronze is a bronze formulated for casting. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. C86200 is the UNS number for this material. Older literature may refer to this material as ASTM Alloy 8B, but this is now discouraged.
It has a very low base cost among cast bronzes. In addition, it has a fairly low thermal conductivity and a very high tensile strength.
The graph bars on the material properties cards below compare C86200 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
Elastic (Young's, Tensile) Modulus
110 GPa 16 x 106 psi
Elongation at Break
21 %
Poisson's Ratio
0.32
Shear Modulus
42 GPa 6.2 x 106 psi
Tensile Strength: Ultimate (UTS)
710 MPa 100 x 103 psi
Tensile Strength: Yield (Proof)
350 MPa 50 x 103 psi
Thermal Properties
Latent Heat of Fusion
190 J/g
Maximum Temperature: Mechanical
160 °C 320 °F
Melting Completion (Liquidus)
940 °C 1730 °F
Melting Onset (Solidus)
900 °C 1650 °F
Specific Heat Capacity
410 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)
9.0 % IACS
Otherwise Unclassified Properties
Base Metal Price
23 % relative
Density
8.0 g/cm3 500 lb/ft3
Embodied Carbon
2.9 kg CO2/kg material
Embodied Energy
49 MJ/kg 21 x 103 BTU/lb
Embodied Water
340 L/kg 41 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
120 MJ/m3
Resilience: Unit (Modulus of Resilience)
540 kJ/m3
Stiffness to Weight: Axial
7.8 points
Stiffness to Weight: Bending
20 points
Strength to Weight: Axial
25 points
Strength to Weight: Bending
22 points
Thermal Diffusivity
11 mm2/s
Thermal Shock Resistance
23 points
Alloy Composition
Among cast copper alloys, the composition of C86200 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 | 3.0 to 4.9 | |
| 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 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
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015