Pure copper, also known as light rose or pink red copper, copper oxide film formed on the surface, the appearance was purple. Copper has many valuable physical and chemical properties, such as its high thermal conductivity and electrical conductivity, its electrical conductivity is second only to silver, thermal conductivity second only to silver and gold; chemical stability, easy to melt, in the atmosphere, fresh water , Seawater has good corrosion resistance; high plasticity, can withstand a variety of cold and hot pressure processing, the disadvantage is the lower strength and hardness, generally do not do structural parts; ductility, copper can be drawn Very thin copper wire, made of thin copper foil; with zinc, tin, lead, manganese, cobalt, nickel, aluminum, iron and other metals to form alloys.① brass ----- copper zinc alloy. Color with the increase of zinc content from yellow to yellow change. Brass mechanical properties higher than pure copper, under normal circumstances will not be corroded; good ductility, is widely used in machinery manufacturing in the production of various structural parts.② bronze ----- copper-tin alloy (in addition to zinc and nickel, add other elements of the Taiwan gold are called bronze). Has good wear resistance, mechanical properties, casting performance and corrosion resistance. Tin content in the alloy is generally not more than l0%, is too high to reduce its plasticity. In addition to tin, tin bronze generally contains a small amount of zinc, lead, phosphorus, nickel and other elements. Zinc can improve the mechanics and mobility of low tin bronze. Lead can improve the wear resistance of bronze and machinability, but reduce its mechanical properties. Nickel can improve the toughness, hardness, wear resistance and fluidity of bronze.Special bronze (Wuxi bronze) --- Steel-based alloy does not contain tin and aluminum, nickel, manganese, silicon, iron, lead and other special alloy elements.③ white copper ----- copper nickel alloy. Divided into the structure of copper-nickel alloy and electrical copper-nickel alloy. Structural copper-nickel alloy high mechanical properties, corrosion resistance is better. Electricians generally have a special copper-nickel alloy thermoelectric properties, in electrical engineering has a wide range of applications. Manganese copper industry, copper, copper, copper is the manganese content of different manganese, they are manufacturing precision electrical measuring instruments, rheostats, thermocouples, electric heaters and other indispensable electrical materials.