HEAT TREATMENT OF STEEL

HEAT TREATMENT OF STEEL

The heat treatment process consists of controlled heating and cooling of component made of either plain carbon steel or alloy steel , for the purpose of changing their structure in order to obtain certain desirable properties like hardness , strength or ductility .The major heat treatment process are follow .

1. Annealing - It consist of heating the component to a temperature slightly above the critical temperature .followed by slow cooling .It reduces hardness and increases ductility .

2. Normalizing  -It is similar to annealing except that the component is slowly cooled in air. It is used to remove the effects of the previous heat treatment process .

3. Quenching -It consists of heating the component to the critical temperature and cooling it rapidly in water or air. It increases the hardness & wear resistance However during the process the component becomes brittle & ductility is reduced .

4. Tempering -It consists of reheating the quenched component to a temperature below the transformation range, followed by cooling at a desired rate . It restore the ductility & reduces the brittleness due to quenching . 

This artical was taken by VB BHANDARI