To have harden the metal and provide it the degree of the toughness and strength, the heat treatment if the metal is required, the heat treatment helps the metal to achieve the desired level strength by changing the micro-structure of the metal. Heating the metal to desired temperature and then cooling same a different rate of cooling help in material to release it pressure and help in achieving the desires softness and toughness.
Making of strong blades such as sword, knife and many industrial cutting blades require different amount of toughness (martensite) and softness. The martensite is achieved by heating the metal to certain temperature and then cooling by the means of immersing the hot metal in oil or water, this rapid change of the heat changes does not allow the carbon atoms to diffuse out of the crystal structure in large enough quantities. When the same material is heated to the desired temperature and then allowed to cool in open air, this cooling rate helps the material desired strength and flexibility.
Hence for making the swords, blades and knifes the differential heat treatment technique is used, because such blades require the desired toughness (Harden) with the strengths to handle the pressure while in application. The differential or selective heat treatment can be achieved by two ways; first by applying the same amount of heat the entire metal and later cooling down the desired areas at different rate. Second applying the different amount of heat at different part of the metal and the allow cooling accordingly. Differential heat treatment can also be achieved by the quenching the complete metal and the tempering only selected area.
We at KERONE has experience of years in helping the industries with their heating needs, we have wide experience in metal heat treatment. For any query write us at [email protected] .