Copper is not only a metal element, but also a transition element. The chemical symbol is Cu, English copy, atomic number 29. Pure copper is a soft metal. When the surface is just cut, it is red orange with metallic luster, and the simple substance is purplish red. Good ductility, high thermal conductivity and conductivity, so it is the most commonly used material in cables and electrical and electronic components. It can also be used as building materials and can form many kinds of alloys. Copper alloy has excellent mechanical properties and low resistivity, among which bronze and brass are the most important. In addition, copper is also a durable metal that can be recycled many times without compromising its mechanical properties