CW622N

CW622N is a copper-zinc-lead-aluminum alloy classified as a duplex alpha-beta brass with fine lead particles and aluminum for tarnish resistance. It is designed for hot extrusion and forming of complex profiles with very good hot workability and fair cold workability.

Chemical Composition

• Copper (Cu) and Zinc (Zn): Approximately CuZn43Pb1Al (about 43% zinc, 1% lead, with aluminum)

• Lead (Pb): Around 1%

• Aluminum (Al): Added for strength and tarnish resistance

• Other minor constituents as per standards

Mechanical and Physical Properties

• Density: About 8.4 g/cm³

• Electrical conductivity: 16.4 MS/m (~28% IACS)

• Thermal conductivity: 126 W/m·K

• Thermal expansion coefficient: 21.6 x 10⁻⁶ /K

• Young’s modulus: 84 GPa

• Melting range: 870–885°C

Fabrication and Machinability

• Machinability: Good (about 80% relative to standard free-cutting brass)

• Hot working capacity: Very good (hot working temperature 625–725°C)

• Cold working capacity: Fair

• Soft annealing temperature: 425–550°C

• Stress relieving temperature: 250–350°C

• Resistance welding (butt welds): Fair

• Brazing: Fair

• Mechanical polishing: Very good

• Electrolytic polishing: Poor

Typical Uses

• Architectural profiles such as handrails, decorative profiles, standard angles, T sections, and channels

• Trim, flooring profiles, and ironmongery

• Hot formed parts with complex shapes or thin walls