Chemical Composition (%)
| Sn | 11.0~13.0 |
|---|---|
| Ni | ≤2.0 |
| Pb | ≤0.7 |
| Zn | ≤0.5 |
| P | ≤0.60 |
| Fe | ≤0.20 |
| Mn | ≤0.2 |
| Cu | 85.0~88.5 |
Mechanical & Physical Properties
| Tensile strength | ≥300 MPa (centrifugal cast); ≥260 MPa (sand cast) |
|---|---|
| Yield strength Rp0.2 | ≥150 MPa (centrifugal / continuous cast) |
| Elongation | ≥6% (centrifugal cast); ≥7% (sand cast) |
| Hardness | ≥90 HBW (centrifugal / continuous cast); ≥80 HBW (sand cast) |
| Density | 8.7 g/cm³ |
Typical Applications
Grade Overview
CuSn12 is a high-tin cast bronze made to EN 1982 / DIN 1705 (CuSn12-C, CC483K), with 11.0-13.0% tin and controlled nickel, lead and phosphorus. The tin-rich matrix gives high hardness and load capacity under boundary lubrication, together with good corrosion resistance. Centrifugal and continuous castings reach at least 300 MPa tensile strength and 90 HBW; sand castings remain above 260 MPa and 80 HBW. It is a bearing grade rather than a structural one: elongation is limited to about 6-7%.
Selecting CuSn12
Choose CuSn12 for heavy, slowly rotating bearing shells, long bushings and worm wheels where load capacity and wear resistance matter more than ductility. Compared with ZCuSn10P1 it carries more tin and therefore more hardness and better load capacity, at higher cost and lower toughness. Where pressure tightness and machinability dominate, ZCuSn5Pb5Zn5 or ZCuSn10Zn2 is easier; where shock loads occur, a leaded bronze such as ZCuPb10Sn10 gives more margin.
Working with CuSn12
Melt under a reducing cover and control tin segregation; high-tin melts are prone to inverse segregation and porosity in thick sections. Feed risers generously, avoid hot spots, and use chills where section thickness changes. The alloy machines cleanly but is abrasive to tooling; no heat treatment is required. Centrifugal casting is preferred for bushings because it produces a dense, fine-grained wall.
Frequently asked questions about CuSn12
Is CuSn12 the same as C90800?
They are close equivalents, not identical designations. CuSn12-C / CC483K is the EN 1982 / DIN 1705 cast designation; UNS C90800 is the nearest American cast bronze. Check the required standard and certificate before substituting.
Can CuSn12 be used for structural parts?
Only where loads are compressive and steady. Elongation is about 6-7% at best, so the grade is intended for bearing shells and bushings, not for parts that see shock or bending.
Sand cast or centrifugal cast?
Centrifugal or continuous casting gives the higher values (≥300 MPa, ≥90 HBW). Sand casting is used for larger or more complex shapes and is rated at ≥260 MPa and ≥80 HBW.
Data compiled from current standards; for selection reference only. Ordering is subject to the standard and the mill certificate. Data source: Shenyang Yuheng Metal Manufacturing Co., Ltd. — yuhengmetal.com.
Related cast copper alloy grades
ZCuZn25Al6Fe3Mn3 · ZCuSn10P1 · ZCuAl10Fe3 | All 52 grades in the library