Which materials can be used to make squirrel-cage rotor conductors?

The materials used for squirrel-cage rotor conductors depend on the size and power requirements of the induction motor:

• Aluminum: For motors up to approximately 300 kilowatts, the squirrel cage is often constructed as an aluminum casting that incorporates the conductors, end rings, and a cooling fan.1
• Copper, Aluminum, or Brass: For larger motors, the squirrel cage is typically composed of bars made from these materials, which are then welded or brazed to end rings of a similar material.1

These conductors are placed in slots within the rotor's steel laminations and are shorted together at each end by conducting end rings. Because the conductors are short-circuited in this manner, they do not require electrical insulation from the rotor iron, making the design both rugged and economical to produce.1