UNS C92800 Leaded Tin Bronze
C92800 bronze is a bronze formulated for casting. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. C92800 is the UNS number for this material. Additionally, the common industry name is 76-16-5.
It has a very low ductility among cast bronzes. In addition, it has a very high embodied energy and a fairly high base cost.
The graph bars on the material properties cards below compare C92800 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
100 GPa 14 x 106 psi
Elongation at Break
1.0 %
Poisson's Ratio
0.35
Rockwell B Hardness
80
Shear Modulus
37 GPa 5.4 x 106 psi
Tensile Strength: Ultimate (UTS)
280 MPa 40 x 103 psi
Tensile Strength: Yield (Proof)
210 MPa 30 x 103 psi
Thermal Properties
Latent Heat of Fusion
170 J/g
Maximum Temperature: Mechanical
140 °C 290 °F
Melting Completion (Liquidus)
960 °C 1750 °F
Melting Onset (Solidus)
820 °C 1500 °F
Specific Heat Capacity
350 J/kg-K 0.084 BTU/lb-°F
Thermal Expansion
18 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
9.0 % IACS
Electrical Conductivity: Equal Weight (Specific)
9.3 % IACS
Otherwise Unclassified Properties
Base Metal Price
36 % relative
Density
8.7 g/cm3 540 lb/ft3
Embodied Carbon
4.1 kg CO2/kg material
Embodied Energy
67 MJ/kg 29 x 103 BTU/lb
Embodied Water
430 L/kg 52 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
2.5 MJ/m3
Resilience: Unit (Modulus of Resilience)
210 kJ/m3
Stiffness to Weight: Axial
6.4 points
Stiffness to Weight: Bending
18 points
Strength to Weight: Axial
8.8 points
Strength to Weight: Bending
11 points
Thermal Shock Resistance
11 points
Alloy Composition
Among cast copper alloys, the composition of C92800 bronze is notable for containing comparatively high amounts of lead (Pb) and tin (Sn). Lead is used to improve machinability and bearing properties, at the cost of toxicity. It also adds pressure tightness to castings. Tin is used to improve strength, bearing properties, and corrosion resistance against certain types of media. It also places certain constraints on cast part design, so as to avoid porosity problems.
| Cu | 78 to 82 | |
| Sn | 15 to 17 | |
| Pb | 4.0 to 6.0 | |
| P | 0 to 1.5 | |
| Ni | 0 to 0.8 | |
| Zn | 0 to 0.8 | |
| Sb | 0 to 0.25 | |
| Fe | 0 to 0.2 | |
| S | 0 to 0.050 | |
| Si | 0 to 0.0050 | |
| Al | 0 to 0.0050 | |
| res. | 0 to 0.7 |
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
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015