Why are stators in induction motors made from thin insulated steel laminations?

In induction motors, the stator is constructed from thin, insulated silicon steel laminations to improve efficiency by minimizing energy loss.

Because a voltage is induced along the axial length of the steel core during operation, it creates circular currents known as eddy currents. If the core were a solid piece of metal, these currents would flow freely, resulting in significant eddy-current losses—a form of wasted energy dissipated as heat. By using thin sheets coated with an insulating varnish, the conducting path for these currents is broken, which effectively limits the magnitude of the eddy currents and reduces overall power loss.1