Copper-nickel alloy, copper and nickel are silver-white, with metallic luster, hence the name white copper.The strength, corrosion resistance, hardness, resistance and thermoelectric properties of pure copper and nickel can be significantly improved, and the temperature coefficient of resistivity can be reduced. Therefore, white copper has better mechanical and physical properties than other copper alloys, good ductility, high hardness, beautiful color, corrosion resistance and deep drawing properties. It is widely used in shipbuilding, petrochemical industry, electrical appliances, instrumentation, medical machinery, daily necessities, handicrafts and other fields, and is also an important resistance and thermocouple alloy. The disadvantage of white copper is that nickel is a scarce strategic material, which is expensive.
Among copper alloys, white copper is widely used as corrosion-resistant structural parts in shipbuilding, petroleum, chemical industry, construction, electric power, precision instruments, medical instruments, musical instruments and other departments because of its excellent corrosion resistance and easy to shape, process and weld. Certain white copper also has special electrical properties, which can be used to make resistance elements, thermocouple materials and compensation wires. Non-industrial white copper is mainly used to make decorative handicraft.
Industrial white copper can be divided into structural white copper and precision resistance alloy white copper (electrical white copper).
(1) Structural white copper: Structural white copper is characterized by good mechanical properties, corrosion resistance and beautiful color. Among structural white copper, the most commonly used are B30, B10 and zinc white copper. Structural white copper is widely used in manufacturing precision machinery, chemical machinery and ship components.
(2) White Copper for Precision Resistance Alloy (Electrical White Copper): White Copper for Precision Resistance Alloy (Electrical White Copper) has good thermoelectric properties. BMn3-12 manganese copper, BMn40-1.5 Kang copper, BMn43-0.5 Kang copper and new Kang copper with manganese instead of nickel are manganese white copper with different manganese content. Manganese white copper is a precise resistance alloy. This kind of alloy has high resistivity and low temperature coefficient of resistivity. It is suitable for making standard resistor and precision resistor. It is used to manufacture precision electrical instruments, rheostats, instruments, precision resistors, strain gauges and other materials. The thermoelectric potential of Kang Tong and Kao Tong is high. They can also be used as thermocouples and compensating wires.