In the future, with the in-depth development of energy efficient, intelligent manufacturing, and green production in the global manufacturing industry, China's electrical steel demand will undergo new changes.

As the industry with the largest consumption of non oriented electrical steel in China (according to incomplete statistics, the annual consumption of electrical steel exceeds 4 million tons), the small and medium-sized electrical industry has been committed to transformation and upgrading in recent years, and has made certain achievements. From the perspective of motor efficiency, ultra efficient motors such as the YE4 series have been promoted and applied, and the IE5 super first-class motor project has been established and started research and development. From the perspective of motor lightweight, small lightweight motors such as high-power ultra-high-speed motors and high-power density motors have been developed. Some products have been applied in fields such as compressors, posing new requirements for silicon steel sheet thinning, reducing loss, and improving magnetic induction strength. From the perspective of the application of new materials for electrical machines, the electrical machine industry has cooperated with universities to carry out research on the application of new magnetic materials. For example, silicon steel scraps, melon seeds, and other waste materials are processed into powder metallurgy, and then molded and sintered into motor iron cores. The loss will be less than 2.1W/kg, and the magnetic induction will be greater than 1.7 Tesla. It is expected that the demand for silicon steel such as W250, W270, and W310 will increase in the future.

Cold rolled non oriented electrical steel refers to cold rolled electrical steel containing 2.9% to 3.5% Si, whose crystal structure has certain regularity and directionality. Generally, it refers to a single oriented silicon steel sheet with a Gaussian texture, that is, a silicon steel with a (110) crystal plane parallel to the rolling plane and a [001] crystal direction parallel to the rolling direction. There are also cold rolled dual oriented (cubic texture {100}) silicon steels. Function: Cold rolled oriented silicon steel, also known as cold rolled transformer steel, is used to manufacture various transformer cores.

Manufacturing process of non oriented electrical steel

The key to producing silicon steel with Gaussian texture is to utilize secondary recrystallization. In order to achieve secondary recrystallization, it is usually necessary to add normal grain growth inhibitors, such as MnS, to the alloy. The grain growth inhibitor can be dispersed in the alloy matrix in a mixed form, effectively preventing the normal growth of the matrix crystal during secondary recrystallization. At the same time, it is also required to be easily removed during subsequent high-temperature annealing to avoid deteriorating the magnetic properties of the product. In secondary recrystallization, the oriented nuclei of secondary grain growth are mainly generated by appropriate cold rolling processes and recrystallization annealing. Because phase transformation can disrupt grain orientation, it is crucial to maintain a single phase during heat treatment.

Hot rolled plates should be cold rolled as soon as possible after normalizing and pickling. If they are parked for a long time, solid carbon and nitrogen precipitate in the steel to form an unstable second phase, which weakens the effect of carbon and nitrogen pinning dislocations during cold rolling. After annealing, the size of AlN precipitated increases and the magnetism decreases.

1) A high reduction cold rolling method using AlN as the main inhibitor;

2) A secondary cold rolling method using MnS as the main inhibitor.