What is recrystallization annealing heat treatment?

Recrystallization annealing is a heat treatment process, and its definition, purpose, process, and characteristics are as follows:

definition:

Recrystallization annealing is a process of heating a workpiece that has undergone cold deformation processing to a temperature above the recrystallization temperature, holding it for a certain period of time, and then cooling it to cause recrystallization of the workpiece, thereby eliminating work hardening.

Usually, this annealing is carried out for cold deformed pure metals and alloys without phase transformation, in order to restore their plasticity.

Purpose:

Eliminate work hardening after cold deformation to facilitate continued processing.

Obtain the required structure, eliminate internal stress, reduce hardness, and improve plasticity in the finished product after cold deformation.

Fully soften steel that has not undergone complete hot processing.

Process:

Heat the workpiece to a temperature higher than its recrystallization temperature (usually within the range of 650-750 ℃, i.e. 150-250 ℃ above the recrystallization temperature).

Maintain the temperature for a certain period of time to allow the deformed grains to recrystallize into uniform equiaxed grains.

Cool in an appropriate manner.

characteristic:

Organization and performance undergo unidirectional irreversible changes.

During the recrystallization annealing process, as a result of recovery and recrystallization, internal stress is eliminated, and the microstructure transforms from cold deformed fibrous structure to fine grain like structure.

The strength of the metal decreases, the plasticity increases, and the plastic deformation ability is restored.

Influencing factors:

The grain size of the recrystallized annealed structure mainly depends on the cold working deformation, annealing temperature, and holding time.

In summary, recrystallization annealing is an important heat treatment process widely used in the processing of metal materials to improve their properties and structure.