CW722R is a duplex high tensile brass with a restricted aluminium content to facilitate soldering and brazing. Sometimes referred to as a manganese bronze, CW722R has additions of iron, tin and manganese that benefit the physical and mechanical attributes of the alloy.
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) |
UTS Max (N/mm2) |
PS Min (N/mm2) |
Elongation Min (%) |
Hardness Min |
Hardness Max |
| Round (Dia) |
|
40 |
75 |
440 |
– |
220 |
18 |
– |
– |
| Hex (A/F) |
|
35 |
60 |
440 |
– |
200 |
18 |
– |
– |
| Square (A/F) |
|
35 |
60 |
440 |
– |
220 |
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 |
| Technique |
Suitability |
| 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 |
| Oxyacetylene Welding |
Not Recommended |
| Gas Shielded Arc Welding |
Not Recommended |
| Resistance welding: Spot and Seam |
Not Recommended |
| Butt |
Fair |
