Chemical Composition (%)
| Sn | 9.0~11.0 |
|---|---|
| Zn | 1.0~3.0 |
| Cu | Balance |
Mechanical & Physical Properties
| Tensile strength | ≥245 MPa (chill cast) |
|---|---|
| Elongation | ≥6% (chill cast) |
| Hardness | ≥80 HBW (chill cast) |
| Density | 8.8 g/cm³ |
Typical Applications
Grade Overview
Cast tin-zinc bronze used for valve bodies, cocks, pump bodies, gears, impellers and worm wheels - medium-duty castings rather than heavy bearing work. Replacing part of the tin with zinc markedly improves castability and pressure tightness, so castings are dense and leak-resistant, while corrosion resistance, wear resistance and machinability stay at a good level; sand-cast tensile strength is about 240 MPa with elongation of at least 8%. It is a well-balanced general-purpose tin bronze. Strength and hardness are only moderate - about 245 MPa and 80 HBW in chill castings - so it cannot carry very high loads or high-speed heavy duty, and its corrosion resistance is below that of the aluminium bronzes. Use it for medium-load pipe fittings and valve parts; control zinc burn-off and segregation when melting, and avoid long-term service in hot steam if the zinc content is on the high side. Its combination of pressure tightness and moderate cost also makes it a practical choice wherever a bronze valve or pump casting has to be produced reliably in quantity.
Data compiled from current standards; for selection reference only. Ordering is subject to the standard and the mill certificate.