Annealing

Annealing refers to treatments that reduce the hardness of steel or provides a structure that facilitates machining operations, both cutting and plastic forming. Annealing operations are used to give steel a microstructure that facilitates further machining and predictable strength properties. Many annealing operaqtions are not carried out by the component manufacturer, but by the steel producer. Examples of this are the annealing of semi-finished products such as flat-rolled steel bar and tube, forgings and castings.

Ref. Steel and its Heat Treatment – A Handbook (8.2)