Copper-nickel alloys are copper-based alloys with nickel as the main additive element. Silver white, metallic luster, so also known as white copper.
Because of infinite solid solution between copper and nickel, when the nickel content exceeds 16%, the color of the alloy becomes white as silver. The higher the nickel content, the whiter the color. The content of nickel in copper-nickel alloys is generally 25%.
Copper-nickel alloy has the characteristics of high strength, corrosion resistance, high hardness, low resistance and thermoelectricity, and can also reduce the temperature coefficient of resistivity. Therefore, compared with other copper alloys, copper-nickel alloys have excellent mechanical and physical properties, good ductility, high hardness, beautiful color, corrosion resistance and deep drawing properties. They are widely used in shipbuilding, petrochemical industry, electrical appliances, instrumentation, medical equipment, daily necessities, handicrafts and other fields, and are also important resistance and thermocouple alloys. The disadvantage of white copper is that nickel, the main additive element, is a scarce strategic material.
Copper-nickel binary alloy (i.e. binary white copper) is called ordinary white copper. In common white copper, the letter B denotes the content of nickel, such as: B5 denotes about 5% of nickel and the rest about copper. Model B0.6, B19, B25, B30.