MakeItFrom.com
Menu (ESC)

UNS C93500 (Alloy 3C) Leaded Tin Bronze

C93500 bronze is a bronze formulated for casting. Cited properties are appropriate for the as-fabricated (no temper or treatment) condition. C93500 is the UNS number for this material. Additionally, the common industry name is 85-5-9-1. Older literature may refer to this material as ASTM Alloy 3C, but this is now discouraged.

It has a fairly high electrical conductivity among cast bronzes. In addition, it has a fairly low tensile strength and a moderately low embodied energy.

The graph bars on the material properties cards below compare C93500 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 15 x 106 psi

Elongation at Break

15 %

Poisson's Ratio

0.35

Shear Modulus

38 GPa 5.5 x 106 psi

Tensile Strength: Ultimate (UTS)

220 MPa 32 x 103 psi

Tensile Strength: Yield (Proof)

110 MPa 16 x 103 psi

Thermal Properties

Latent Heat of Fusion

180 J/g

Maximum Temperature: Mechanical

160 °C 320 °F

Melting Completion (Liquidus)

1000 °C 1830 °F

Melting Onset (Solidus)

850 °C 1570 °F

Specific Heat Capacity

360 J/kg-K 0.085 BTU/lb-°F

Thermal Conductivity

70 W/m-K 40 BTU/h-ft-°F

Thermal Expansion

18 µm/m-K

Electrical Properties

Electrical Conductivity: Equal Volume

15 % IACS

Electrical Conductivity: Equal Weight (Specific)

15 % IACS

Otherwise Unclassified Properties

Base Metal Price

31 % relative

Density

9.0 g/cm3 560 lb/ft3

Embodied Carbon

3.0 kg CO2/kg material

Embodied Energy

49 MJ/kg 21 x 103 BTU/lb

Embodied Water

350 L/kg 42 gal/lb

Common Calculations

Resilience: Ultimate (Unit Rupture Work)

28 MJ/m3

Resilience: Unit (Modulus of Resilience)

59 kJ/m3

Stiffness to Weight: Axial

6.3 points

Stiffness to Weight: Bending

17 points

Strength to Weight: Axial

6.9 points

Strength to Weight: Bending

9.1 points

Thermal Diffusivity

22 mm2/s

Thermal Shock Resistance

8.5 points

Alloy Composition

Among cast copper alloys, the composition of C93500 bronze is notable for containing a comparatively high amount of lead (Pb). Lead is used to improve machinability and bearing properties, at the cost of toxicity. It also adds pressure tightness to castings.

Copper (Cu) 83 to 86
Lead (Pb) 8.0 to 10
Tin (Sn) 4.3 to 6.0
Zinc (Zn) 0 to 2.0
Phosphorus (P) 0 to 1.5
Nickel (Ni) 0 to 1.0
Antimony (Sb) 0 to 0.3
Iron (Fe) 0 to 0.2
Sulfur (S) 0 to 0.080
Silicon (Si) 0 to 0.0050
Aluminum (Al) 0 to 0.0050
Residuals 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