In general, the purpose of annealing is to soften the material so that it can be processed further. Annealing dramatically reduces the residual internal stresses that develop from hot working operations such as forging, rolling, stamping, etc. Because the material can be softened considerably by using an appropriate annealing cycle, both its tensile strength and yield strength are typically reduced. The amount that it is reduced by depends upon the material in question, the prior mechanical and thermal history, and the annealing cycle used.
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