C3712
C3712, known as Engraving brass, falls under the category of 60/40 alpha-beta brasses. It incorporates varying amounts of lead to enhance its free machining capabilities. This particular brass variety is extensively employed in crafting engraved plates and plaques, manufacturing builders’ hardware, and producing gears. It’s important to note that it’s not suitable for acid etching work, for which the single phase alpha brasses are better suited.
CHEMICAL COMPOSITION
| Elements | Min (%) | Max (%) |
| Cu | 58.00 | 62.00 |
| Pb | 0.25 | 1.20 |
| Fe+Sn | – | 0.80 |
| Zn | Remainder | |
MECHANICAL PROPERTIES ACCORDING TO EN12164 (AS PER TEMPER R410)
| Range (mm) | From | To | UTS Min (MPa) | PS Min | Elongation Min (%) | Hardness Min | Hardness Max |
| Round (Dia) | 6 | 75 | 315 | – | 15 | – | – |
| Hex (A/F) | 6 | 70 | 70 | – | 15 | – | – |
| Square (A/F) | 6 | 60 | 315 | – | 15 | – | – |
| Rectangle (Thickness) | 6 | 50 | 315 | – | 15 | – | – |
| PHYSICAL PROPERTIES | |
| Melting Point – Liquidus°F | 1650 |
| Melting Point – Solidus°F | 1630 |
| Density lb/cu in. at 68°F | 0.304 |
| Specific Gravity | 8.41 |
| Electrical Conductivity % IACS at 68°F | 27 |
| Thermal Conductivity Btu/ sq ft/ ft hr/ °F at 68°F | 69 |
| Coefficient of Thermal Expansion 68-57210⁻⁶ per °F (68 – 572°F) | 11.6 |
| Specific Heat Capacity Btu/ lb /°F at 68°F | 0.09 |
| Modulus of Elasticity in Tension ksi | 15000 |
| Modulus of Rigidity ksi | 5600 |
| FABRICATION PROPERTIES | |
| Technique | Suitability |
| Soldering | Excellent |
| Brazing | Good |
| Oxyacetylene Welding | Not Recommended |
| Gas Shielded Arc Welding | Not Recommended |
| Coated Metal Arc Welding | Not Recommended |
| Not Recommended | Not Recommended |
| Seam Weld | Not Recommended |
| Butt Weld | Fair |
| Capacity for Being Cold Worked | Fair |
| Capacity for Being Hot Formed | Excellent |
| Machinability Rating | 70 |
