processingdetails

Case Hardening

Case hardening，also can be called as surface hardening ,is a simple processing method, which is applied to harden the surface of a metal, often a low carbon steel, by infusing elements into the material's surface, forming a thin layer of a harder alloy. It is less complex than hardening and tempering. Case hardening is usually done after the part in question has been formed into its final shape, but can also be done to increase the hardening element content of bars to be used in a pattern welding or similar process. The term face hardening is also used to describe this technique, when discussing modern armour. This technique is used for steels with a low carbon content. Carbon is added to the outer surface of the steel, to a depth of approximately 0.03mm. One advantage of this method of hardening steel is that the inner core is left untouched and so still processes properties such as flexibility and is still relatively soft.

The process of case hardening has two stages. In the stage one, the steel is heated to red heat. It may only be necessary to harden one part of the steel and so heat can be concentrated in this area. In the second stage: the steel is removed from the brazing hearth with blacksmiths tongs and plunged into case hardening compound and allowed to cool a little. The case hardening compound is high in carbon.