to Metals
to Copper alloys
Dr. Dmitri Kopeliovich
According to the Unified Numbering System (UNS):
Cast Copper-Nickel Alloys (Copper-Nickels, Cupro-Nickels) are copper alloys, containing 9-31% of nickel (Ni) as the major alloying element. Cast Copper-Nickel alloys are designated with the numbers from C96000 through C96999.
Cast Copper-Nickel alloys may contain up to 8% of tin (Sn), up to 1.4% of iron (Fe) , up to 1% of manganese (Mn), up to 1% of niobium (Nb) and up to 1.1% of beryllium (Be)as additional alloying elements.
Cast Copper-nickel-zinc alloys form a separate group called nickel silvers.
Cast Copper-Nickel-Zinc Alloys (Nickel Silvers) are copper alloys containing 12.5-25.5% of nickel (Ni) and 2.5-21% of zinc (Zn) as the major alloying elements. Cast Copper-Nickel-Zinc alloys are designated with the numbers from C97000 through C97999.
Wrought Copper-Nickel-Zinc alloys may contain 2.5-5% of tin (Sn) and 2-9.5% of lead (Pb) as additional alloying elements.
Cast Copper-Nickel alloys and most of cast Copper-Nickel-Zinc alloys have mono-phase structure (α-phase).
Cast Copper-Nickel and cast Copper-Nickel-Zinc alloys have moderate mechanical strength and high ductility combined with very good corrosion resistance (particularly in sea water).
Iron, manganese and niobium are added to the cast Copper-Nickel alloys for increasing their hardness and strength.
Separate group of copper-nickel alloys is Spinodal Bronzes: copper-nickel-tin alloys possessing high mechanical strength due to a controlled heat treatment called Spinodal decomposition.
Cast Copper-Nickel alloys are used for manufacturing pump bodies, bearings, bushings, steam fittings, boat part, valves and fittings resistant to corrosion in sea water, plastic molds tooling.
Cast Copper-Nickel alloys (Nickel Silvers) are used in decorative applications and for manufacturing marine furniture, sanitary fittings, fittings for food processing, valves, pumps, window hardware, components of musical instruments.
| UNS Designation | Trade mark | Ni,% | Fe,% | Zn,% | Sn,% | Others,% | Cu,% |
|---|---|---|---|---|---|---|---|
| C96300 | Copper-Nickel | 18.0-22.0 | 0.5-1.5 | - | - | Nb0.5-1.5Mn 0.25-1.5 | balance |
| C96400 | 70-30 Copper-Nickel | 28.0-32.0 | 0.25-1.5 | - | - | Nb0.5-1.5 | balance |
| C96970 | Copper-Nickel | 8.5-9.5 | 0.5 max. | - | 5.5-6.5 | - | balance |
| C97300 | Nickel Silver (12% Ni) | 11.0-14.0 | 1.5 max. | 17.0-25.0 | 1.5-3.0 | Pb8.0-11.0 | balance |
| C97600 | Nickel Silver (20% Ni) | 19.0-21.5 | 1.5 max. | 3.0-9.0 | 3.5-4.5 | Pb3.0-5.0 | balance |
| C97800 | Nickel Silver (25% Ni) | 24.0-27.0 | 1.5 max. | 1.0-4.0 | 4.0-5.5 | Pb1.0-2.5 | balance |