Chemical Composition (%)
| Sn | 2.0~4.0 |
|---|---|
| Zn | 9.0~13.0 |
| Pb | 3.0~6.0 |
| Cu | Balance |
Mechanical & Physical Properties
| Tensile strength | ≥215 MPa (chill cast) |
|---|---|
| Elongation | ≥10% (chill cast) |
| Hardness | ≥60 HBW (chill cast) |
| Density | ≈8.7 g/cm³ |
Typical Applications
Grade Overview
An economical cast tin bronze in which a good deal of the tin is replaced by zinc, used mainly for low-pressure valves, pipe fittings and pump parts in seawater, fresh water and steam. The higher zinc content gives good fluidity, excellent casting behaviour and easy machining while retaining a measure of corrosion resistance; strength and hardness are both modest, so this is a grade chosen for fabricability and cost rather than for load capacity. Chill-cast tensile strength is at least 215 MPa with elongation of at least 10% and hardness of at least 60 HBW. Corrosion resistance holds up only at low pressure and low flow velocity, and dezincification and selective corrosion remain a risk in long-term seawater contact. Use it for simple castings with modest pressure duty; check the medium and temperature, and move to aluminium bronze or cupronickel when better corrosion resistance is needed. Because strength is low, castings should be generously sectioned and pressures kept modest; the alloy pours and machines easily, which keeps production simple.
Data compiled from current standards; for selection reference only. Ordering is subject to the standard and the mill certificate.