Copper Alloy C94300
UNS C94300
C94300 (Alloy 3E) is a very high-lead tin bronze in the cast bronze family (C90000–C95999), with roughly 30% lead dispersed through a copper–tin matrix to form a soft, self-lubricating bearing surface.
Reference datasheet — C94300 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the M07 condition
C94300 tempers and conditions
C94300 is supplied in 4 conditions, soft to hard. M07 is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As sand cast | Pick for one-off or complex-geometry bearing housings and thrust washers per ASTM B584. | 90 | 186 | 15 | 48 HB | 9 % IACS |
As centrifugally cast | Pick for large-diameter sleeve bearings and bushing blanks needing dense, sound walls. | 100 | 200 | 12 | 52 HB | 9 % IACS |
As plaster cast | Pick for repeat-run small bushings where a chill mold gives finer structure and better as-cast dimensions. | 100 | 195 | 12 | 52 HB | 9 % IACS |
M07Default As continuous cast | Default stocked form: continuous-cast solid bar and cored tube per ASTM B505, machined directly into bushings. | 105 | 205 | 12 | 55 HB | 9 % IACS |
What is C94300?
C94300 (Alloy 3E) is a very high-lead tin bronze in the cast bronze family (C90000–C95999), with roughly 30% lead dispersed through a copper–tin matrix to form a soft, self-lubricating bearing surface. It is used for slow-speed, heavily loaded plain bearings where conformability and dirt embedability matter more than strength, and is supplied as sand, permanent-mould, centrifugal and continuous castings. Default-condition values are 105 MPa yield, 205 MPa tensile, 12% elongation and 55 HB. The lead content makes it effectively unweldable and limits surface finish quality; C94400 offers more strength with less lead. C94300 has a density of 9.29 g/cm³ (0.336 lb/in³), heavier than 99% of copper alloy grades. It melts at 762°C (1,404 °F). C94300 has a yield strength of 105 MPa (15.2 ksi) and a tensile strength of 205 MPa (29.7 ksi) — weaker than 85% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 72 GPa (10.4 Msi).
What is C94300 used for?
- Heavy-duty bushings
- Slow-speed bearings
- Machine bases
Advantages
- Easy to machine — 90/100, better than 98% of copper alloy grades
- Low embodied carbon — 3 kg CO₂/kg, better than 97% of copper alloy grades
Limitations
- Low stiffness — 72 GPa (10.4 Msi), worse than 100% of copper alloy grades
- Difficult to weld — 8/100, worse than 100% of copper alloy grades
- Limited formability — 5/100, worse than 98% of copper alloy grades
- Hard to polish — 55/100, worse than 97% of copper alloy grades
- Low strength — 105 MPa (15.2 ksi), worse than 85% of copper alloy grades
C94300 properties
Typical room-temperature values for C94300-M07; bars are the position among copper alloy grades.
Physical3
C94300 has a density of 9.29 g/cm³ (0.336 lb/in³), heavier than 99% of copper alloy grades. It melts at 762°C (1,404 °F).
Mechanical12
C94300 has a yield strength of 105 MPa (15.2 ksi) and a tensile strength of 205 MPa (29.7 ksi) — weaker than 85% of copper alloy grades. Elongation at break is 12% and the elastic modulus is 72 GPa (10.4 Msi).
Thermal5
C94300 is rated for continuous service to 230°C (446 °F). It conducts heat at 46.7 W/m·K (27 BTU/hr·ft·°F), worse than 72% of copper alloy grades. Thermal expansion is 18.5 µm/m·K (10.3 µin/in·°F).
Electrical3
C94300 conducts electricity at 9 % IACS, worse than 78% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), worse than 76% of copper alloy grades.
Sustainability4
Producing a kilogram of C94300 takes about 45 MJ of energy and emits 3 kg of CO₂ — less than 97% of copper alloy grades. Typical recycled content is 70%.
Manufacturability8
C94300's machinability is excellent (90/100, better than 98% of copper alloy grades); weldability not recommended (8/100); formability not recommended (5/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the copper alloy family
Yield strength against density for every copper alloy grade FabDigit runs. C94300 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C94300
Is C94300 easy to machine?
Extremely free-cutting — use sharp positive-rake tools, high speed, light feeds and plenty of coolant; chips break short but the soft lead phase can smear and load fine finishing tools.
Can C94300 be welded?
Effectively unweldable due to 30% lead — repair by mechanical means or replacement; soft-soldering is acceptable, brazing/fusion welding is not.
Can C94300 be formed, bent or molded?
Casting-only alloy with no cold formability; sand, centrifugal, permanent-mold and continuous casting all work well, but gate for low pouring temperature to limit lead segregation and use adequate risers.
C94300 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CuASTM B584/B505 range | 67 – 72 | 70 |
| Sn | 4.5 – 6 | 5 |
| Pbfree lead phase provides self-lubrication | 29 – 32 | 30 |
| Zn | ≤ 0.8 | |
| Niincl. Co | ≤ 1 | |
| Sb | ≤ 0.8 | |
| Fe | ≤ 0.15 | |
| S | ≤ 0.08 | |
| P | ≤ 0.05 | |
| Al | ≤ 0.01 | |
| Si | ≤ 0.01 |
What surface finishes work on C94300?
Takes tin, silver or nickel plating for corrosion barrier; polishing gives only a moderate luster because of lead smearing, and bearing bores are normally finished by boring, reaming or burnishing rather than grinding.
Surface treatments FabDigit runs on copper alloy parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Equivalent designations
Standards and trade names that resolve to Copper Alloy C94300 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- Alloy 3E
How much does C94300 cost?
C94300 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
C94300 — frequently asked
What is C94300 used for?
C94300 is typically used for heavy-duty bushings, slow-speed bearings and machine bases. In short: highest-lead bearing bronze; self-lubricating at low speed; lowest strength of the family.
What is the yield strength of C94300?
C94300 has a typical yield strength of 105 MPa (15.2 ksi) and a tensile strength of 205 MPa (29.7 ksi) — weaker than 85% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is C94300 easy to machine?
Yes — machinability is rated excellent (90/100, better than 98% of copper alloy grades). Extremely free-cutting — use sharp positive-rake tools, high speed, light feeds and plenty of coolant; chips break short but the soft lead phase can smear and load fine finishing tools.
Can C94300 be welded?
Not readily — weldability is rated not recommended (8/100). Effectively unweldable due to 30% lead — repair by mechanical means or replacement; soft-soldering is acceptable, brazing/fusion welding is not.
What surface finishes work on C94300?
Takes tin, silver or nickel plating for corrosion barrier; polishing gives only a moderate luster because of lead smearing, and bearing bores are normally finished by boring, reaming or burnishing rather than grinding.
Can C94300 be formed, bent or molded?
Casting-only alloy with no cold formability; sand, centrifugal, permanent-mold and continuous casting all work well, but gate for low pouring temperature to limit lead segregation and use adequate risers.
What is the maximum service temperature of C94300?
C94300 is rated for continuous use to about 230°C (446 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C94300-M07 and C94300-M01?
M07 is the default condition — default stocked form: continuous-cast solid bar and cored tube per ASTM B505, machined directly into bushings. M01: pick for one-off or complex-geometry bearing housings and thrust washers per ASTM B584. Yield strength is 105 MPa in M07 versus 90 MPa in M01.
How much does C94300 cost?
C94300 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM B584 — Copper Alloy Sand Castings for General Applications — ASTM International (2022)
- ASTM B505/B505M — Copper Alloy Continuous Castings — ASTM International (2018)
- ASTM B271 — Copper-Base Alloy Centrifugal Castings — ASTM International (2020)
- CDA Alloy Database — C94300 High-Leaded Tin Bronze — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 18 — Friction, Lubrication and Wear Technology — ASM International (1992)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.