The use of copper for the conductor bars and end rings of induction motors in place of aluminum results in attractive improvements in motor energy efficiency. Until recently, die cast motor rotors were universally produced using aluminum because rotor fabrication by aluminum pressure die-casting was an established practice, and copper pressure die-casting was unproven. This section identifies and demonstrates design methods, manufacturing process parameters, and durable mold materials that have enabled economical production of die-cast copper motor rotors.
