Normalization is a type of annealing process used to relieve stress in hardenable steels after cold work (or pouring)  and to improve ductility and toughness properties. The steel is heated slightly above its upper critical temperature and held for sufficient time to allow new, smaller grains to form and high energy grain shapes to coalesce, also known as grain refinement.

Normalization can also eliminate denritic segregation that may remain from the casting process. The steel is air cooled from the normalization temperature, yielding a microstructure that lends the desired toughness and ductility properties with a nominal tensile strength.