C28000
C28000 is a lead-free material that’s well-suited for machining due to its structural composition. It can serve as a cost-effective alternative to traditional lead-containing machining brass, provided that it doesn’t need to meet stringent requirements for mechanical properties and corrosion resistance.
CHEMICAL COMPOSITION
| Elements | Min (%) | Max (%) |
| Cu | 59.00 | 63.00 |
| Pb | – | 0.09 |
| Fe | – | 0.07 |
| Total Others | – | 0.30 |
| Zn | Remainder | |
| (1) Cu + Sum of Named Elements 99.7% min. | ||
MECHANICAL PROPERTIES ACCORDING TO ASTM B36 (AS PER TEMPER HO2)
| Range (Inch) | From | To | UTS Min (ksi) | UTS Max (ksi) | PS Min | Elongation Min (%) | Hardness Min (HRB) | Hardness Max (HRB) |
| Round (Dia) | 0.059 | 2.953 | 58 | 70 | – | – | 52 | 80 |
| Hex (A/F) | 0.118 | 2.756 | 58 | 70 | – | – | 52 | 80 |
| Square (A/F) | 0.118 | 2.362 | 58 | 70 | – | – | 52 | 80 |
| Range (mm) | From | To | UTS Min (MPa) | UTS Max (MPa) | PS Min | Elongation Min (%) | Hardness Min (HRB) | Hardness Max (HRB) |
| Round (Dia) | 1.5 | 75 | 400 | 485 | – | – | 52 | 80 |
| Hex (A/F) | 3 | 70 | 400 | 485 | – | – | 52 | 80 |
| Square (A/F) | 3 | 60 | 400 | 485 | – | – | 52 | 80 |
| PHYSICAL PROPERTIES | |
| Melting Point – Liquidus°F | 1660 |
| Melting Point – Solidus°F | 1650 |
| Density lb/cu in. at 68°F | 0.303 |
| 8.39 | 8.39 |
| Electrical Conductivity % IACS at 68°F | 28 |
| Thermal Conductivity Btu/ sq ft/ ft hr/ °F at 68°F | 71 |
| 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 | 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 | Fair |
| Capacity for Being Hot Formed | Excellent |
| Forgeability Rating | 90 |
| Machinability Rating | 40 |
