C3771, Section brass, is a readily extrudable leaded alpha/beta brass with a small aluminium addition, which gives a bright golden colour. The lead gives free cutting properties. C3771 is available as extruded rods and flats which are typically used in builder’s hardware.
CHEMICAL COMPOSITION
| Elements | Min (%) | Max (%) |
| Cu | 57.00 | 61.00 |
| Pb | 1.00 | 2.50 |
| Sn+Fe | – | 1.00 |
| Zn | Remainder |
MECHANICAL PROPERTIES ACCORDING TO H3250 JIS C3771 (AS PER TEMPER BD)
| Range (mm) | From | To | UTS Min (N/mm²) | PS Min | Elongation Min (%) | Hardness Min | Hardness Max |
| Round (Dia) | 6 | 75 | 315 | – | 15 | – | – |
| Hex (A/F) | 6 | 70 | 315 | – | 15 | – | – |
| Square (A/F) | 6 | 60 | 315 | – | 15 | – | – |
| Rectangle (Thickness) | 6 | 50 | 315 | – | 15 | – | – |
| PHYSICAL PROPERTIES |
| Physical Properties | Metric | English |
| Density | 8.40 g/cc | 0.303 lb/in3 |
| CTE, linear | 26.0 ᶙm/m-˚C | 14.4 ᶙin/in-˚F |
| Specific Heat Capacity | 0.380 J/g-˚C | 0.0908 BTU/lb-˚F |
| Thermal Conductivity | 113 W/m-K | 784 BTU-in/hr-ft²-˚F |
| Melting Point | 880-900 ˚C | 1620 – 1650 ˚F |
| Solidus | 880 ˚C | 1620 ˚F |
| Liquidus | 900 ˚C | 1650˚F |
| FABRICATION PROPERTIES |
| Forming | Suitability |
| Machinability (CuZn39Pb3 = 100 %) | 95.00% |
| Capacity for Being Cold Worked | Poor |
| Capacity for Being Hot Worked | Excellent |
TYPICAL USES
- Architecture
- Builders Hardware
