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Normalizing process

Normalizing ( Air quenching) is a heat treatment process in which steel is heated 40°-50° C above re-crystallization temperature , hold for some time and then air cooled to the room temperature. It is one of the heat treatment process which is used for ferrous materials only. 

Fig. - air cooled steel components

This treatment refine the grain structure and increase uniformity of micro-structure and propertied of hot rolled steel.

 


Normalizing process  use to remove internal stress. It gives rise to the bainite, martensite and perlite. Normalizing require less cost than annealing due to air cooling. Due to normalizing, hardness of steel increase and ductility decrease.

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