Copper-Nickel Alloys (Copper-Nickels, Cupro-nickels) are copper alloys, containing 1.5-45% of nickel (Ni) as the major alloying element. Wrought Copper-Nickel alloys are designated with the numbers from C70000 through C73499.
Wrought Copper-Nickel alloys may contain up to 8% of tin (Sn), up to 4.5% of manganese (Mn), up to 2% of iron (Fe), up to 2.5% of chromium (Cr) and up to 1% of silicon (Si) as additional alloying elements.
Copper-nickel-zinc alloys form a separate group called nickel silvers.
Copper-Nickel-Zinc Alloys (Nickel Silvers) are copper alloys containing 8-25% of nickel (Ni) and 17-45% of zinc (Zn) as the major alloying elements. Wrought Copper-Nickel-Zinc alloys are designated with the numbers from C73500 through C79999.
Wrought Copper-Nickel-Zinc alloys may contain up to 6% of manganese (Mn) as additional alloying element.
Copper-Nickel alloys and most of Copper-Nickel-Zinc alloys have mono-phase structure (α-phase) and possess very good formability in cold and hot states.
Iron, manganese and chromium are added to the wrought Copper-Nickel alloys for increasing their hardness and strength.
The alloys are strengthened by cold work (strain hardening). Ductility of the alloys decreases as a result of cold work.
Copper-Nickel alloys are used for manufacturing coins, sea water equipment, evaporators, heat exchanger tubes, automotive hydraulic and cooling systems.
Copper-Nickel alloys (Nickel Silvers) are used in decorative applications and for manufacturing resistance wire, optical parts, screws, rivets, clips, tableware, electrical contacts.
|UNS Designation||Trade mark||Ni,%||Zn,%||Mn,%||Fe,%||Cu,%|
|C70400||Copper-Nickel 5%||4.8-6.2||1.0 max.||0.3-0.8||1.3-1.7||balance|
|C70600||Copper-Nickel 10%||9.0-11.0||1.0 max.||1.0 max.||1.0-1.8||balance|
|C71000||Copper-Nickel 20%||19-23||1.0 max.||1.0 max.||1.0 max.||balance|
|C71500||Copper-Nickel 30%||29-33||1.0 max.||1.0 max.||0.4-1.0||balance|
|C74500||Nickel Silver 65-10||9.0-11.0||balance||0.5 max.||0.25 max.||63.5-66.5|
|C75200||Nickel Silver 65-18||16.5-19.5||balance||0.5 max.||0.25 max.||63.0-66.5|
|C75400||Nickel Silver 65-15||14.0-16.0||balance||0.5 max.||0.25 max.||63.5-66.5|
|C75700||Nickel Silver 65-12||11.0-13.0||balance||0.5 max.||0.25 max.||63.5-66.5|
|C77000||Nickel Silver 55-18||16.5-19.5||balance||0.5 max.||0.25 max.||53.5-56.5|