Process Annealing

Process Annealing of Metals Explained

Process Annealing
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Process, or sub-critical, annealing is used to counteract the hardening effects of a cold-working operation on a metal.

After significant cold work, a piece may become too brittle to safely continue the working process. Process annealing involves heating the metal piece to a temperature anywhere below its austenitizing temperature until stresses have been removed from the lattice structure and then slowly cooling the material to avoid introducing new stresses.

 This effectively anneals the material without significantly changing the phase fractions that have been established by prior heat treating processes.