What is Annealing ? Why It is used ?

Annealing is one of the most important and widely used operations in the heat treatment of steel.

Annealing is the process of heating the metal above its critical temperature and cooling slowly after hold it for sometime to increase the usability of the material.

The purpose of Annealing is to obtain one or more of the following effects :

1. Soften the steel

2. Improve Machinability

3. Increase or restore ductility and toughness.

4. Relieve Internal Stress

5. Reduce or eliminate structural in homogeneity.

6. Refine grain Size.

7. Prepare Steel for subsequent heat treatment.

also see :

Types of Annealing

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