Induction heating, is a process for increase temperature in a workpiece, made in material with electromagnetic property, place into an alternate electromagnetic field.
The principle of induction heating is similar to a transformer.
The coil (inductor), becomes primary circuit winding and it surround workpiece that will be heat.
The workpiece is secondary circuit winding, made as single coil in short circuit.
Supply by alternating current primary winding (inductor) creates a magnetic field, that induces alternating current (eddy currents) in the workpiece. Flowing of eddy currents cause heating in workpiece (Joule effect).
The depth of eddy currents flow in workpiece and the heating distribution as consequence, depends on current frequency in the inductor and electromagnetic material properties (permeability and resistivity).
Induction heating, compare with other traditional heating systems (gas or electric furnaces), it is the way with more advantages as: fast heating for high temperature too, heating precisions, heating available immediately when required (no delay time), no large space need, etc.