Induction heating occurs when passing alternating magnetic fields through conductive materials. This is accomplished by placing an alternating current carrying coil around or in close proximity to the materials. The alternating fields generate eddy currents in the materials. These currents interact with the resistance of the material to produce heat. Heat coils can be designed in conjunction with proper frequency, to pin-point heat zones without affecting surrounding conductive metals. Induction heat treating is used on a range of metal parts, including bar and tubing, bearings, axel shafts, camshafts, gears and sprockets.