CA104

CA104 is a wrought high-strength aluminium bronze alloy featuring about 10% aluminium, 4–5% Nickel, and 4–5% Iron. It is renowned for excellent strength, toughness, resistance to corrosion (especially in seawater), high wear resistance, and retention of mechanical properties at cryogenic temperatures.

Chemical Composition (Typical)

• Copper (Cu): Balance

• Aluminium (Al): 8.5% – 11.0%

• Nickel (Ni): 4.0% – 5.5%

• Iron (Fe): 4.0% – 5.0%

• Manganese (Mn): Up to 1%

• Zinc (Zn): Up to 0.4%

• Silicon (Si): Up to 0.25%

• Tin (Sn): Up to 0.20%

• Lead (Pb): Up to 0.05%

• Total Impurities: Up to 0.5%

Mechanical Properties

• Tensile Strength (UTS): 650 – 700 MPa (minimum, up to 820 MPa for some tempers)

• Yield Strength (0.2% Proof): 320 – 400 MPa (typical)

• Elongation: 10–25%

• Hardness: 170–210 HB (Brinell, varies by temper)

• Modulus of Elasticity: 115 GPa

Physical Properties

• Density: 7.5 g/cm³

• Melting Point: 1035–1075°C

• Thermal Conductivity: 33–46 W/m·K

• Electrical Conductivity: 7–10% IACS

• Thermal Expansion Coefficient: 18×10−6/°C

Fabrication and Joining

• Good for hot working (850–975°C); cold formability is limited

• Machinability rating: About 20% (relative to free cutting brass)

• Brazing: Fair; MIG/TIG welding: Good; Resistance welding: Good

• Soldering: Not recommended

Key Features

• Excellent resistance to corrosion, erosion, and abrasion

• High mechanical strength and toughness

• Non-sparking and non-magnetic

• Retains properties at sub-zero temperatures

• Used in marine hardware, pump and valve components, bearings, bushes, gears, high-strength fasteners, and aerospace/defence applications