Aluminum alloys for motor windings

During the last few years, several developments have aroused great interest in the electrical industry. Two of the most important are: (1) the increasing price of copper; and (2) the development of new aluminum alloys for wire. A quick comparison of costs of aluminum and copper ingot or redraw rod since 1940 (Figure 1) clearly shows the economic reasons for replacing copper with aluminum in conductor applications. Even though there have been fluctuations, the cost advantage of aluminum is apparent.