Bearing Bronze
C93200 — High-Leaded Tin Bronze (SAE 660 Bearing Bronze)
The standard cast bearing bronze: good anti-friction behaviour, easy machining and tolerance of marginal lubrication.
Grade overview
C93200, widely known as SAE 660, is the most commonly specified cast bronze for plain bearings and bushings. Its microstructure of a tin-bronze matrix with dispersed lead gives it good embeddability and anti-seizing behaviour, and it machines very well.
It is available as sand castings and as continuous-cast or centrifugally cast bar and tube from which bushings are machined. Its strength is moderate, so very high loads, impact or severely corrosive service may call for other grades such as aluminum bronzes.
Alloy family and identification
Cast copper-tin-lead-zinc alloy, UNS C93200, commonly called SAE 660, “bearing bronze” or 83-7-7-3. Contains significant lead.
| Item | Detail |
|---|---|
| UNS designation | C93200 |
| Common name | High-Leaded Tin Bronze (SAE 660 Bearing Bronze) |
| Alloy family | Bearing Bronze |
| Type | Cast copper-tin-lead-zinc alloy |
Typical composition
| Element | Nominal limit, wt % |
|---|---|
| Copper (Cu) | 81.0 – 85.0 |
| Tin (Sn) | 6.3 – 7.5 |
| Lead (Pb) | 6.0 – 8.0 |
| Zinc (Zn) | 2.0 – 4.0 |
| Nickel (Ni, incl. Co) | 1.0 max |
| Iron (Fe) | 0.20 max |
| Antimony (Sb) | 0.35 max |
| Phosphorus (P) | 0.15 max |
| Sulfur (S) | 0.08 max |
Reference data only – typical or nominal values from published specifications, not a guarantee of supplied material. Confirm against the current edition of the applicable specification, the product form and condition, and the material test certificate. Technical review by the company is required before publication or reliance.
Typical mechanical properties
Mechanical property values are intentionally not published here. They vary with specification, product form, size and temper or condition and will be added only once the governing specification and condition are confirmed. Request the applicable specification or test certificate with your inquiry.
Physical properties
Physical properties (density, thermal and electrical data) are not listed until verified against an authoritative datasheet. Contact us for current reference data.
Corrosion and wear considerations
Good resistance to fresh water and many lubricants; moderate in sea water. Lead content makes it unsuitable for potable-water contact. Load capacity and PV limits depend on lubrication, shaft hardness and design – these must be assessed for the application rather than assumed.
Machinability and fabrication
Excellent machinability, among the best of the copper alloys. Typically supplied oversized from cast bar for finish machining. Not normally welded; consult before attempting repairs.
Common industrial applications
- Plain bearings and bushings
- Thrust washers and wear rings
- Pump and machinery bearings
- Gear and slide components under moderate load
- General engineering wear parts
Examples only. Suitability must be confirmed for the actual operating environment.
Available product forms
Sizes, tolerances and stock are not published and must be confirmed with the company.
Relevant products
Standards and specifications
- ASTM B505/B505M – continuous castings
- ASTM B584 – sand castings
- SAE 660 (trade designation)
Verify against the current edition and the exact product form before specifying.
Certification and inspection options
Material test certificates, chemical analysis, dimensional reports and third-party inspection can be requested with your inquiry. What can be supplied for C93200 is confirmed with the company for each order; no certificate is implied by this page.
Related grades
Frequently asked questions
Is C93200 the same as SAE 660?
Yes – SAE 660 is the common trade designation for UNS C93200.
Can C93200 be used for potable water?
No. It contains lead; lead-free alternatives such as C89833 are considered for that purpose, subject to the applicable drinking-water requirements.
Need C93200 in a specific form?
Share your grade, dimensions, quantity and technical requirements with our team.