CW722R
CW722R is categorized as a duplex high tensile brass alloy with a deliberately limited aluminum content, a feature designed to improve its soldering and brazing capabilities. Occasionally likened to manganese bronze, CW722R distinguishes itself by incorporating additional elements such as iron, tin, and manganese. These additives contribute to enhancing both the physical and mechanical properties of the alloy, making it well-suited for various applications.
CHEMICAL COMPOSITION
| Elements | Min (%) | Max (%) |
| Cu | 56.50 | 58.50 |
| Pb | 0.80 | 1.60 |
| Al | – | 0.10 |
| Fe | 0.20 | 1.20 |
| Mn | 0.80 | 1.80 |
| Ni | – | 0.30 |
| Sn | 0.20 | 1.00 |
| Total others | – | 0.30 |
| Zn | Remainder | |
MECHANICAL PROPERTIES ACCORDING TO EN12164 CW722R (AS PER TEMPER R440)
| Range (mm) | From | To | UTS Min (N/mm²) | PS Min (N/mm²) | Elongation Min (%) | Hardness Min | Hardness Max |
| Round (Dia) | 40 | 75 | 440 | 200 | 18 | – | – |
| Hex (a/F) | 35 | 60 | 440 | 200 | 18 | – | – |
| Square (A/F) | 35 | 60 | 440 | 200 | 18 | – | – |
| Rectangle (Thickness) | 40 | 50 | 440 | 200 | 18 | – | – |
| PHYSICAL PROPERTIES | |
| Melting Point | 940°C |
| Density 8.42 | g/cm³ |
| Specific Heat | 380 J/Kg°K |
| Thermal conductivity (RT) | 88 W/m°K |
| Thermal expansion coefficient (20-200°C) | 20 x 10-6 |
| Electrical conductivity | 18% IACS |
| Electrical Resistivity | 0.082 ohm mm²/m |
| FABRICATION PROPERTIES | |
| Hot Working Temperature Range | 700-750°C |
| Hot Formability | Very Good |
| Cold Formability | Poor |
| Machinability rating (free cutting brass = 100) | 75% |
| Annealing Temp. Range | 425-600°C |
| Stress Relieving Temp. Range | 225-350°C |
| Soldering | Very Good |
| Brazing | Very Good |
| Oxy-acetylene welding | Not Recommended |
| Gas-shielded arc welding | Not Recommended |
| Resistance welding: Spot and Seam | Not Recommended |
| Butt | Fair |
