processingdetails

Annealing

Annealing is a kind of heat treatment wherein a material is altered, which is commonly used in metallurgy and materials science. It is used to cause changes in its properties such as strength and hardness and produces conditions by heating to above the recrystallization temperature, maintaining a suitable temperature, and then cooling. Annealing is used to induce ductility, soften material, relieve internal stresses, refine the structure by making it homogeneous, and improve cold working properties. Full annealing is the process of slowly raising the temperature about 50 oC (90 oF) above the Austenitic temperature line A3 or line ACM in the case of Hypoeutectoid steels (steels with < 0.77% Carbon) and 50 oC (90 oF) into the Austenite-Cementite region in the case of Hypereutectoid steels (steels with > 0.77% Carbon).

In the cases of copper, steel, silver, and brass, this process is performed by substantially heating the material (generally until glowing) for a while and allowing it to cool. Unlike ferrous metals—which must be cooled slowly to anneal—copper, silver and brass can be cooled slowly in air or quickly by quenching in water. In this fashion the metal is softened and prepared for further work such as shaping, stamping, or forming.