Tin bronze, gunmetal & bell bronze: chemical composition
Tin bronzes are copper–tin alloys in which tin raises strength, hardness and wear resistance and gives good sliding behaviour against steel. Gunmetals (Rotguss) add zinc and lead for better castability, pressure tightness and machinability, while bell bronze sits at the high-tin end, where the metal becomes hard, brittle and resonant.
Plain bearings, bushings, worm wheels, wear rings and sleeves, pump and valve bodies and sea-water fittings for marine and general engineering; high-tin bell bronze for church bells.
Grades compared (mass %)
| Grade | Material no. | Standard | Si | P | S | Ni | Cu | Fe | Sn | Zn | Pb | Al | Sb |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CuSn10-C | CC480K | EN 1982 | ≤ 0.02 | ≤ 0.20 | ≤ 0.05 | ≤ 2.00 | 88.0–90.0 | ≤ 0.20 | 9.00–11.0 | ≤ 0.50 | ≤ 1.00 | ≤ 0.01 | ≤ 0.20 |
| CuSn12-C | CC483K | EN 1982 | ≤ 0.01 | ≤ 0.60 | ≤ 0.05 | ≤ 2.00 | 85.0–88.5 | ≤ 0.20 | 11.0–13.0 | ≤ 0.50 | ≤ 0.70 | ≤ 0.01 | ≤ 0.15 |
| C91000 | UNS C91000 | ASTM B505 | ≤ 0.005 | ≤ 1.50 | ≤ 0.05 | ≤ 0.80 | 84.0–86.0 | ≤ 0.10 | 14.0–16.0 | ≤ 1.50 | ≤ 0.20 | ≤ 0.005 | ≤ 0.20 |
| CuSn5Zn5Pb5-C | CC491K | EN 1982 | ≤ 0.01 | ≤ 0.10 | ≤ 0.10 | ≤ 2.00 | 83.0–87.0 | ≤ 0.30 | 4.00–6.00 | 4.00–6.00 | 4.00–6.00 | ≤ 0.01 | ≤ 0.25 |
| CuSn7Zn4Pb7-C | CC493K | EN 1982 | ≤ 0.01 | ≤ 0.10 | ≤ 0.10 | ≤ 2.00 | 81.0–85.0 | ≤ 0.20 | 6.00–8.00 | 2.00–5.00 | 5.00–8.00 | ≤ 0.01 | ≤ 0.30 |
| G-CuSn10Zn | 2.1086 | DIN 1705 (withdrawn) | – | ≤ 0.05 | ≤ 0.10 | ≤ 2.00 | 86.0–89.0 | ≤ 0.25 | 9.00–11.0 | 1.00–3.00 | ≤ 1.50 | – | ≤ 0.30 |
| CuSn20 | – | – | – | – | – | 79.0–81.0 | – | 19.0–21.0 | – | – | – | – | |
| CuSn12Ni2-C | CC484K | EN 1982 | ≤ 0.01 | 0.05–0.40 | ≤ 0.05 | 1.50–2.50 | 84.5–87.5 | ≤ 0.20 | 11.0–13.0 | ≤ 0.40 | ≤ 0.30 | ≤ 0.01 | ≤ 0.10 |
Tin bronze, gunmetal & bell bronze: cast and machined in-house
Tin bronze castings by sand casting, and by centrifugal casting for bushings, wear rings and sleeves, machined in the group's own CNC machine shop, with the chemistry of every heat verified by optical emission spectrometer and EN 10204 3.1 certificates. Church bells are the craft the foundry started with.
- Sand casting at our foundry in Mandra, Attica; centrifugal casting for bushings, sleeves and liners
- Heat treatment at the foundry (water, oil or air quench); CNC machining in our machine shop in Perama
- Spectrometer analysis of every heat, mechanical testing and NDT
- EN 10204 3.1 inspection certificates; ISO 9001 (both plants) and ISO 14001 (foundry) certified
All alloy families
For information only, without warranty: limits per the cited standard or, where stated, typical or house values; ≈ marks a comparable grade, not an equivalent. The current edition of the standard, the purchase order and the drawing govern.