What is the term used to describe the rotor core of an induction motor that is made from slotted sheet steel?

The term that describes the rotor core of an induction motor made from slotted sheet steel is "laminations." Laminations refer to thin sheets of electrical steel that are stacked together to form the core of the rotor. This construction technique is employed to reduce energy losses due to eddy currents, which are loops of electrical current that can occur within the core material when it is subjected to alternating magnetic fields. By using laminated sheets instead of a solid piece of metal, the resistance to these eddy currents is increased, leading to improved efficiency in the motor's operation.

This design not only aids in preserving the overall performance of the motor but also helps in managing heat generation within the core, as larger solid materials would trap more heat and potentially impair operation over time. Laminated cores are common in both rotor and stator designs across various types of electric motors to enhance their efficiency and performance.