The main difference between normalizing and annealing is temperature, cooling rate, use effect, cycle.The normalizing temperature is higher and the annealing temperature is lower.The cooling rate of normalizing is faster than that of annealing.Normalizing cycle is short, easy to operate;The annealing cycle is long and the operation is troublesome.
The use effect is different, after carburizing treatment, normalizing can eliminate the network cementite, annealing can not.For the steel with carbon content below 0.25x, the hardness and cutting performance can be improved after normalizing, but it can not be improved by annealing.Annealing is to heat steel to a certain temperature and keep heat at this temperature, and then slowly cool to room temperature, annealing has complete annealing, spheroidizing annealing, stress free annealing and so on.Normalizing is the heat treatment process of heating steel parts to the critical temperature above 30-50℃, holding for an appropriate time, cooling in static air is called normalizing.The main purpose of normalizing is to refine the structure, improve the properties of steel, and get close to the equilibrium state of the structure.Compared with the annealing process, the main difference is that the cooling rate of the normalizing is slightly faster, so the production cycle of the heating treatment is short.So annealing and normalizing can also meet the performance requirements of parts, as far as possible to choose normalizing.
