This section introduces copper conductivity materials (coppers and copper alloys) for electrical applications and provides details of properties and uses.
Copper has the highest conductivity of any non-precious metal. This, combined with its high ductility, good machinability, high strength, ease of jointing and good resistance to corrosion, makes copper the first choice as a conductor for electrical applications.
High conductivity copper is the most common form of the metal and it is widely available with consistent high quality. It is the first choice for the manufacture of bulk conductors such as cables, busbars, transformer windings and motor stators and rotors. However, for other electrical applications, such as connector parts, commutators and catenary wires, the mechanical properties may need to be enhanced by the addition of appropriate alloying elements. The ease with which copper can form alloys with other elements results in the availability of a very wide range of materials suitable for the full range of electrical applications.
As mechanical properties are enhanced by the addition of alloying elements, there is a trade off with a reduction in electrical conductivity.
The graph below shows how the addition of various alloying elements affects the conductivity of copper.
This graph plots tensile strength and conductivity for different copper alloys.
A downloadable reference publication, High Conductivity Copper for Electrical Engineering (Publication Cu0232) describes the electrical and mechanical properties of high conductivity copper and copper alloys that are intended for use in electrical applications. It is primarily aimed at electrical engineers rather than metallurgists, but gives the basic metallurgical detail needed to understand the processing requirements of alloys.
Watch the video giving an overview of the properties that make copper the material of choice for conductivity applications, and the trade off between enhancing certain properties and reducing electrical conductivity.