Pure Copper:
It is red, so called red copper. The density of pure copper is 8.96, smelting point is1,083 degree centigrade, with good electric conductivity, heat conductivity, ductility and corrosion resistance. It is mainly used to make machine, bus, cable, switch settings, transformer and heat exchanger, pipe, plate of radiator of solar heat equipment.
Copper Alloy: It is an alloy whose basic element is pure copper, adding into one or more other element. General copper alloy is divided into brass, bronze, cupronickel, three classifications.
Brass:
Copper alloy main adding element is zinc, with beautiful yellow, collectively called brass. Copper zinc binary alloy is called general brass or simple brass. Over three element brass called special brass or complicated brass. Brass alloy lower than 36 percent is made up by solid solution, copper alloy has feature of good cold processing property, such like brass with 30 percent of zinc is made to cartridge case, which is called cartridge case brass or seven three brass. Brass alloy with zinc element between 36 percent and 42 percent is made up by solid solution, which is the most common. Six four brass with 40 percent of zinc in order to improve the property of general brass, adding other element, such like aluminum, nickel, manganese, tin, silicon, lead, etc. Aluminum can improve the strength, hardness, corrosion resistance of brass, but the plasticity is low, which is suitable for ship condenser and other corrosion resistance parts. Tin can improve the strength and corrosion resistance of sea water, so called navy brass, which is applied in ship heat processing equipment and propeller, etc. Lead can improve the machinability of brass, this brass is used to make clock parts. Brass castings are used to make valve and pipe parts and so on. Fire hydrant anti-explosion crescent spanner for ship is cast by brass and aluminum.
Bronze:
Originally, it is copper tin alloy, except for brass, cupronickel, after that , copper alloy is collectively called bronze and it is the first element in front of the name of bronze. Tin bronze is typical of good casting property, anti-friction and mechanical property, which is suitable to make bearing, worm gear, gear, etc. Lead bronze is bearing material which widely used in modern machine and grinder. Aluminum bronze is characterized by high strength, wear resistance, corrosion resistance, which is applied in casting high load gear, axle sleeve, propeller for ship. Beryllium and phosphorous bronze high elasticity, good electric conductivity, which is suitable to make precise spring and electric connecting element, beryllium is also used to make non spark tools in coal mine and oil depot.
Cupronickel:
It is copper alloy whose main adding element is nickel. Copper nickel binary alloy is called general cupronickel, cupronickel alloy with manganese, iron, zinc, aluminum is called complicated cupronickel. Cupronickel for industry is divided into structural cupronickel and electrician cupronickel two large classification.
