CW711R

CW711R is a naval brass alloy renowned for good corrosion resistance, high ductility, and excellent electrical and thermal conductivity. It is particularly valued for its high impact strength and creep resistance, suitable for hot forging, pressing, and machining. Compared to CW712R, CW711R typically features slightly less copper and tin and higher lead content that enhances machinability.

Chemical Composition

• Copper (Cu): 59.50 – 61.50%

• Lead (Pb): 1.30 – 2.20%

• Tin (Sn): 0.50 – 1.00%

• Iron (Fe): Up to 0.10%

• Nickel (Ni): Up to 0.30%

• Zinc (Zn): Balance

• Other elements: Up to 0.20%

Mechanical Properties

• Tensile Strength: Minimum 410 MPa (varies with shape and form)

• Elongation: Minimum 18%

• Hardness: Depends on temper and form

Physical Properties

• Density: 8.44 g/cm³

• Melting Point: Solidus ~1630°F (887°C), Liquidus ~1650°F (899°C)

• Electrical Conductivity: Approximately 26% IACS

• Thermal Conductivity: About 67 BTU/(ft²·hr·°F)

• Coefficient of Thermal Expansion: 11.8 × 10⁻⁶ per °F

Fabrication and Applications

• Excellent soldering and brazing properties

• Limited welding options

• Poor cold workability, excellent hot workability (forgeability rating 90)

• Machinability rating: 70 (relative)

• Used for marine hardware, valve parts, pump components, and machined precision parts