Aluminum is rich in resources, with lower price than copper. Its conductivity is second only to copper, but its density is only 30% of that of copper. Therefore, when replacing copper with aluminum, if the resistance is kept constant, the weight of aluminum used is less than half of that of copper, which is advantageous. If the resistance is kept constant, the diameter of the aluminum wires winding is about 30% larger than that of the copper wire. Therefore, the groove shape should be appropriately increased, and the iron consumption should be increased, which is a disadvantage.



Aluminum is easy to oxidize. As soon as the oxide film is formed, it can prevent aluminum from continuing to oxidize. Aluminum is not easy to be corroded in the air. Due to the existence of oxide film, the difficulty of copper aluminum or aluminum aluminum wires welding is increased, so special welding process must be adopted, which has accumulated certain experience in the motor industry of our country.

The common electromagnetic wire of motor winding is copper wire, and aluminum wire is also used. Round wire is used for small section, and the diameter of the round wire used in small motors is generally less than 1.6mm, so as to facilitate winding and embedding. When the cross section is large, several parallel wires or several parallel wires can be used, or flat wires can be used. When the pole winding is manufactured, the aluminum wires winding strip with larger cross section is used.