PURPOSE: To increase the starting torque of an induction motor by forming a rotor of an iron-fiber mixed aluminum, and altering the iron-fiber mixing rate of the surface of the rotor.

CONSTITUTION: The stator 1 of an induction motor has a laminated armature core 11 and an armature winding 12, and the rotor 2 is formed of bodies 21, 22 formed of iron-fiber mixed aluminum and a rotational shaft 23. In this case, a portion 21 near the surface of the rotor reduces a mixing rate (60∼50%), and a portion 22 near the shaft 23 increases the mixing rate (80∼60%). Further, a thin layer 24 of good conductive metal (copper) is metallized to the surface of the rotor 2 to readily generate an eddy current. Thus, the rotor 2 operates as a low inertial rotor, the surface layer 24 and the portion 21 near the surface readily generate and feed eddy currents, and the inner portion 22 effectively forms a magnetic path.