UNS C27400 yellow brass has a copper content of not less than 62%, CuZn37 is the major brass alloy for the cold forming process. Even though brasses with lower Zinc content have better cold forming properties, CuZn37 is the most used alloy. Reasons for this are on the one hand economical due to lower price of Zinc compared to copper on the other hand the forming properties of this alloy meet the demand of many applications.
CHEMICAL COMPOSITION
| Elements | Min (%) | Max (%) |
| Cu | 61.00 | 64.00 |
| Pb | – | 0.10 |
| Fe | – | 0.05 |
| Total Others | – | 0.30 |
| Zn | Remainder |
MECHANICAL PROPERTIES ACCORDING TO ASTM B927 (AS PER TEMPER HO2)
| Range (Inch) | From | To | UTS Min (Ksi) | PS Min (Ksi) | Elongation Min (%) | Hardness Min | Hardness Max |
| Round (Dia) | 0.059 | 0.500 | 53 | 33 | 10 | – | – |
| 0.500 | 1.000 | 48 | 30 | 13 | – | – |
| 1.000 | 2.953 | 43 | 28 | 15 | – | – |
| Hexagon (A/F) | 0.118 | 0.500 | 53 | 33 | 10 | – | – |
| 0.500 | 1.000 | 48 | 30 | 13 | – | – |
| 1.000 | 2.756 | 43 | 28 | 15 | – | – |
| Square (A/F) | 0.118 | 0.500 | 53 | 33 | 10 | – | – |
| 0.500 | 1.000 | 48 | 30 | 13 | – | – |
| 1.000 | 2.362 | 43 | 28 | 15 | – | – |
| Rectangle (Thickness) | 0.118 | 0.500 | 53 | 33 | 10 | – | – |
| 0.500 | 1.000 | 48 | 30 | 13 | – | – |
| 1.000 | 1.969 | 43 | 28 | 15 | – | – |
| Range (mm) | From | To | UTS Min (MPa) | PS Min (MPa) | Elongation Min (%) | Hardness Min | Hardness Max |
| Round (Dia) | 1.5 | 12 | 365 | 230 | 10 | – | – |
| 12 | 25 | 330 | 205 | 13 | – | – |
| 25 | 75 | 295 | 195 | 15 | – | – |
| Hex (A/F) | 3 | 12 | 365 | 230 | 10 | – | – |
| 12 | 25 | 330 | 205 | 13 | – | – |
| 25 | 70 | 295 | 195 | 15 | – | – |
| Square (A/F) | 3 | 12 | 345 | 170 | 10 | – | – |
| 12 | 25 | 310 | 115 | 20 | – | – |
| 25 | 50 | 275 | 105 | 20 | – | – |
| Rectangle (Thickness) | 3 | 12 | 345 | 170 | 10 | – | – |
| 12 | 25 | 310 | 115 | 20 | – | – |
| 25 | 50 | 275 | 105 | 20 | – | – |
| PHYSICAL PROPERTIES |
| Melting Point – Liquidus°F | 1680 |
| Density lb/cu in. at 68°F | 0.31 |
| Specific Gravity | 8.44 |
| Electrical Conductivity % IACS at 68°F | 27 |
| Thermal Conductivity Btu/ sq ft/ ft hr/ °F at 68°F | 67 |
| Coefficient of Thermal Expansion 68-57210⁻⁶ per °F (68 – 572°F) | 11.4 |
| 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 | Excellent |
| Oxyacetylene Welding | Good |
| Gas Shielded Arc Welding | Fair |
| Coated Metal Arc Welding | Not Recommended |
| Spot Weld | Good |
| Seam Weld | Not Recommended |
| Butt Weld | Good |
| Capacity for Being Cold Worked | Excellent |
| Capacity for Being Hot Formed | Fair |
| Machinability Rating | 35 |
