The workpiece is placed in an inductor made by spiral hollow copper tubes. The inductive current is formed on the workpiece surface after the copper tubes fed with medium or high-frequency AC. The surface or a part of the workpiece is heated rapidly (800-1000 C can be heated in a few seconds, and the unheated part for the workpiece is still close to room temperature) and then sprayed (immersed) with water or oil to cool after several seconds, so that the surface or heated part of the workpiece reaches the required hardness. The method is widely used in gearing making to obtain a good wear resistance on gear surface.