IS 4640

IS 4640 typically refers to a copper alloy known as Nickel Aluminium Bronze, which corresponds to specifications such as AMS 4640 or UNS C63000 in international standards.

Chemical Composition (Typical for AMS 4640 / DIN 2.0966)

• Copper (Cu): Balance (~78-83%)

• Aluminium (Al): 9.0-11%

• Iron (Fe): 2.0-4.0%

• Manganese (Mn): About 1.5%

• Nickel (Ni): 4.0-5.5%

• Silicon (Si): ~0.25%

• Tin (Sn): ~0.20%

• Zinc (Zn): ~0.30%

• Others: Minor amounts

Mechanical Properties (Typical Values)

• Tensile Strength: 772 - 814 MPa (varies by size and heat treatment)

• Yield Strength: Approx. 420 - 517 MPa

• Elongation: Generally 15% or higher

• Hardness: Brinell 210 - 230 HB

• Modulus of Elasticity: 117 GPa

Physical Properties

• Density: Approx. 7.53 g/cm³

• Melting Point: Solidus ~1895°F (1035°C), Liquidus ~1930°F (1054°C)

• Electrical Conductivity: About 7% IACS

• Thermal Conductivity: Around 22.6 Btu·ft/(hr·ft²·°F)

Applications

• Aerospace bearings and bushings

• Marine pump components and shafts

• Valve seats and spindles

• Industrial machinery is exposed to corrosion and wear