The use of induction technology may seem very new, but it is actually a very well-known process that has been in used since the early to mid-part of the 1800s. First development my Michael Faraday, induction heating was discovered, through the use of winding wire around a magnetic coil.
These two coils of wire that are wound around the same magnetic core and with the application of an electric current, they produce an electromagnetic field. This only occurs when the current flows in opposite directions and without any contact between the primary and secondary winding.
The actual use of induction technology in working with metals wasn’t fully developed until the development of the electric motors that were able to drive induction furnaces that were large enough to be used to melt steel. This same process, including the use of motor generators to provide induction hardening systems, is still in use today.
The Process Used
With modern induction hardening processes, it is possible to specifically treat certain areas of a part or component or to treat the entire piece. The area of the part that is to be treated will be held or rotated through the electromagnetic field to create the desired internal molecular changes.
At this point, and without any direct contact with any heat source and the metal, the part is immediately quenched. As only the surface layer of the part is impacted by the process, there is no change to the internal structure of the part or components, which means there is no change in the natural properties of the metal part or component except for the additional strength and durability of the surface layer.
By using the process of induction hardening, parts can quickly and easily be hardened at a low cost of processing. Additionally, the areas treated will have increased wear resistance, providing a longer life cycle and increased resistance to pitting and fatigue.