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What is Heat Treatment of Metals and What are Its Process?

 Any Solid metal normally has a definite cell (unit cell) shape and size at a certain energy state, but in some metals the shape as well as the size change from one energy state to another. The energy state is usually changed by adding or taking away heat. Such a process is called Heat Treatment . 


It may therefore be defined as an operation or combination of operations involving the heating and cooling of metals or alloys in the solid state to produce certain desired properties. All heat treatment processes may be considered to consist of three main parts :

1. The heating of the metal to the predetermined temperature.

2. The soaking of the metal at that temperature until the structure becomes uniform throughout the mass. 

3. The cooling of the metal at some predetermined rate to cause the formation of  desirable structures within the 

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