Xiaomi Auto said at the press conference that the company's high-speed motor used oriented silicon steel for the first time. According to reports, oriented silicon steel is mainly used in the manufacturing of transformers (iron cores), which can improve the energy efficiency of transformers and reduce transmission losses. Due to high technical barriers, domestic enterprises that can produce oriented silicon steel are mainly concentrated in large state-owned steel enterprises and a small number of private enterprises.

Zhongshi Industrial Research Institute said that all kinds of products motor generally use non-oriented silicon steel production, at present, China's large motor (thermal power, wind power) is trying to use non-bottom oriented silicon steel as raw material production motor, the future is expected to achieve technological breakthroughs, for oriented silicon steel to provide new growth space. In addition, the stator and rotor in the drive motor of new energy vehicles can now be paired with oriented silicon steel and non-oriented silicon steel, reducing energy consumption and improving performance. The vigorous development and promotion of new energy vehicles is expected to provide potential growth space for oriented silicon steel. According to the data, by the end of 2020, there are 21 oriented silicon steel production enterprises in China, including 3 state-owned enterprises and 18 private enterprises.

China's silicon steel industry started late, from imitation to independent research and development has paid great hardships, automotive silicon steel and Japan and other countries still have a certain gap. At present, China can mass produce a full series of automotive silicon steel products with a thickness of 0.20mm-0.35mm, basically meeting the needs of new energy passenger cars and buses. On the one hand, the performance of the motor requires high efficiency, that is, in order to obtain the maximum battery life, high magnetic induction silicon steel is required; On the other hand, greater speed is needed, the high frequency caused by high speed will increase the consumption of iron loss, and with the increase of speed, the stress of the rotor will also increase, therefore, the need for low iron loss, high strength silicon steel.

The core loss in the motor is mainly divided into: hysteresis loss and eddy current loss, in which hysteresis loss is proportional to the area of the hysteresis loop, that is, proportional to the frequency; Eddy current loss is proportional to the square of frequency, proportional to the square of thickness, and inversely proportional to resistivity. Because the high speed of the motor requires high frequency, it is basically impossible to reduce the hysteresis loss. The eddy current loss can be improved from two aspects: thickness and resistivity. First, the thinner the material is, the less eddy current loss is. The second is to add silicon to the material to increase resistivity and reduce eddy current loss.

When the thickness is reduced, the high frequency iron loss of silicon steel is greatly reduced. When the silicon steel has a high enough yield strength, it often shows a large iron loss, and high yield strength and high frequency and low iron loss are often not compatible. This is in contrast to the requirements of low iron loss, high magnetic induction, high tensile strength and other requirements for silicon steel used in new energy automobile motors: in the case of low iron loss, the pursuit of good magnetic properties and mechanical properties is the future direction of motor development.

At present, the material selection of the drive motor is mainly from the Angle of speed and frequency to consider the thickness of silicon steel, the higher the speed, the higher the frequency, the thinner the silicon steel. New energy vehicle manufacturers and steel mills adopt strategic cooperation to purchase in the form of direct supply. The market for automotive silicon steel circulation is small, traders rarely participate. Under the guidance of the policy, the thin-gauge automotive silicon steel models will be more abundant, and the production capacity and output will gradually expand. At that time, the closed market will become an open market, bringing more investment opportunities for traders, while the steel mill actively layout new energy automobile silicon steel, traders should also actively respond to enter the track in advance, occupy the circulation market.