Copper Nickel

copper nickel is an alloy of copper that contains nickel and strengthening elements, such as iron and manganese. Copper nickel is highly resistant to corrosion in seawater, because its electrode potential is adjusted to be neutral with regard to seawater. Because of this, copper nickel is used for piping, heat exchangers and condensers in seawater systems as well as marine hardware, and sometimes for the propellers, crankshafts and hulls of premium tugboats, fishing boats and other working boats. A more familiar common use of copper nickel is in silver-colored modern circulation coins. A typical mix is 75% copper, 25% nickel, and a trace amount of manganese. In the past, true silver coins were debased with cupronickel. Despite high copper content, cupronickel is silver in color. It is used in thermocouples, and resistors whose resistance is stable across changes in temperature contain the 55% copper-45% nickel alloy constantan. Monel metal is a nickel-copper alloy, containing minimum 63% nickel. uses single-core thermocouple cables use a single conductor pair of thermocouple conductors such as iron-constantan, copper constantan or nickel-chromiumnickel-aluminum. These have the heating element of constantan or nickel-chromium alloy within a sheath of copper, copper-nickel or stainless steel. Beginning around the turn of the 20th century, bullet jackets were commonly made from this material. It was soon replaced with gilding metal to reduce metal fouling in the bore. Currently, cupronickel remains the basic material for silver-plated cutlery. It is commonly used for mechanical and electrical equipment, medical equipment, zippers, jewelry items, and as material for strings for string instruments. For high-quality cylinder lock and locking systems, the cylinder core is made from wear-resistant copper nickel.