Heat Treating

Heat treatment is the controlled heating or cooling of material to change its structure in order to obtain certain mechanical properties, such as hardness, strength or ductility. Heat treating processes include Annealing, which heats the material slightly above its critical temperature, then slowly cools it to reduce its hardness and increase its ductility. Normalizing cools the heated material in air to remove the effect of all previous heat treatment processes. Quenching heats the material to its critical temperature, then cools it rapidly in water or air to increase its hardness and wear resistance. Tempering reheats a quenched part to a point below its critical temperature, then cools it at a desired rate to increase its ductility and toughness.