What is Normalization?

Normalization is a heat treatment performed to eliminate the inhomogeneous structure of materials resulting from processes such as forging and rolling and to reduce the grain size. Metals require normalization after many forming methods (such as rolling, forging or cold forming). In the normalization process, the steel is made homogeneous and fine-grained. The normalization process is also known as annealing. Normalization annealing is generally applied to normalize carbon and low alloy steels after forging, rolling or hot casting processes. The normalization process is performed to obtain a homogeneous structure for materials that have lost their homogeneity. Additionally, grain reduction is applied to improve the mechanical properties of steels, to increase the hardness and durability of softened annealed materials, and to facilitate mechanical processing. With normalization annealing, the inhomogeneity in the structure of the material is eliminated and a finer grained structure is obtained. The hardness formed after normalization varies depending on the mechanical properties of the steel and the cooling rate.
How to Perform Normalization Annealing?
For the normalization process, the surface of the material is first cleaned. Normalization heat treatment is performed up to 30-50°C above the A3 or Acm curves, depending on the carbon amount of the material. It is kept at the heat treatment temperature for a certain period of time depending on the diameter and thickness of the part to which normalization is applied. In this heated temperature range, austenitic grains are formed. Austenitic grains are small compared to the previous ferritic structures. After the waiting period, the cooling process of the material takes place. The material can be cooled outside the furnace in calm air. Depending on the type of use, tempering or stress relieving heat treatments can be applied in addition to normalization annealing. After the normalization process, a homogeneous and fine-grained structure is obtained. The material becomes high strength. With the homogeneous and fine-grained structure formed after the normalization process, the mechanical properties of the steel are measured at the same values throughout the entire area of the material. After the normalization process, mechanical processing is easily done.
Advantages of Normalization Process
The advantages of the normalization or annealing process can be listed as follows; The normalization process increases the strength of the material. It provides relief from internal tensions. Flexibility increases with the normalization process. The mechanical, electrical and magnetic properties of the material are improved. Machining ability increases. https://www.aht.com.tr/