copper
An alloy made from pure copper as the base, with one or several other elements. Pure copper is purplish-red and also known as bronze. The density of pure copper is 8.96, the melting point is 1083℃, and it has excellent electrical conductivity, thermal conductivity, ductility and corrosion resistance. It is mainly used to make electrical equipment such as generators, busbars, cables, switchgears, transformers, etc., as well as heat-conducting equipment such as heat exchangers, pipes, flat-panel collectors for solar heating devices. Commonly used copper alloys are divided into three categories: brass, bronze and cupronickel.
brass
Common copper alloys are classified into three categories: The copper-zinc binary alloy is called ordinary brass or simple brass.brass, bronze, and white copper. is called special brass or complex brass. Brass alloys containing less than 36% zinc are composed of solid solution and have good cold working properties. For example, brass containing 30% zinc is often used to make bullet casings, commonly known as bullet casing brass or seven-three brass. Brass alloys with zinc content between 36 and 42% are composed of and solid solution, of which the most commonly used is the six-four brass with zinc content of 40%. In order to improve the properties of ordinary brass, other elements are often added, such as aluminum, nickel, manganese, tin, silicon, lead, etc. Aluminum can improve the strength, hardness and corrosion resistance of brass, but reduce the plasticity, so it is suitable for seagoing condenser pipes and other corrosion-resistant parts. Tin can improve the strength of brass and the corrosion resistance to seawater, so it is called naval brass and is used for ship thermal equipment and propellers. Lead improves the machinability of brass; this free-cutting brass is often used in watch parts. Brass castings are often used to make valves and pipe fittings, etc.
bronze
Originally referred to as copper-tin alloys, all copper alloys other than brass and white copper are referred to as bronze and are often prefixed with the name of the first primary added element.Tin bronze has good casting performance, anti-friction performance and good mechanical performance, and is suitable for manufacturing bearings, worm gears, gears, etc. Lead bronze is a bearing material widely used in modern engines and grinders. Aluminum bronze has high strength, good wear resistance and corrosion resistance, and is used for casting high-load gears, bushings, marine propellers, etc. Beryllium bronze and phosphor bronze have high elastic limit and good electrical conductivity, and are suitable for manufacturing precision springs and electrical contact elements. Beryllium bronze is also used to make non-sparking tools used in coal mines and oil depots.
cupronickel
A copper alloy with nickel as the main additive element. The copper-nickel binary alloy is called ordinary cupronickel; the cupronickel alloy with manganese, iron, zinc, aluminum and other elements is called complex cupronickel. Industrial cupronickel is divided into two categories: structural cupronickel and electrical cupronickel. The characteristics of structural cupronickel are good mechanical properties and corrosion resistance, and beautiful color. This cupronickel is widely used in the manufacture of precision machinery, chemical machinery and ship components. Electrical cupronickel generally has good thermoelectric properties. Manganin, constantan and test copper are manganese cupronickel with different manganese content, and are used in the manufacture of precision electrical instruments, varistors, precision resistors, strain gauges, thermocouples, etc.