As an important soft magnetic material, cold rolled non-oriented silicon steel's electromagnetic properties are significantly affected by the addition of various alloying elements.
First of all, silicon is one of the most critical alloying elements in cold rolled non-oriented silicon steel. The addition of silicon can effectively increase the resistivity of silicon steel, thereby reducing eddy current losses. As the silicon content increases, the magnetic permeability of silicon steel will increase, resulting in a corresponding reduction in hysteresis loss in the alternating magnetic field. For example, when the silicon content gradually increases from a low level, the energy conversion efficiency of silicon steel sheets in electrical equipment such as motors will be significantly improved, reducing the waste of electrical energy in the magnetic conversion process. However, excessive silicon content will cause the brittleness of silicon steel to increase and the processing performance to deteriorate, so its content needs to be controlled within a reasonable range, usually between 0.5% and 3.5%.
Secondly, the addition of aluminum element also plays an important role in the electromagnetic properties of cold rolled non-oriented silicon steel. Aluminum, similar to silicon, can increase resistivity and reduce eddy current losses. At the same time, aluminum can also refine the grains, improve the organizational structure of silicon steel, and thereby increase the magnetic permeability. Adding an appropriate amount of aluminum can make the magnetic properties of silicon steel more uniform and stable, and maintain good electromagnetic conversion efficiency under different magnetic field strengths. However, too much aluminum will form some compounds that are not conducive to magnetic properties and reduce the saturation magnetization of silicon steel, so the amount of aluminum added is generally around 0.3% - 1.5%.
Furthermore, manganese element mainly plays the role of solid solution strengthening and deoxidation in cold rolled non-oriented silicon steel. The presence of manganese can increase the strength of silicon steel, making it less likely to deform during processing. In terms of electromagnetic properties, an appropriate amount of manganese can slightly increase the magnetic permeability of silicon steel, but if the manganese content is too high, it will cause the hysteresis loss of silicon steel to increase, because manganese will promote the formation of some phases that are not conducive to magnetic properties. Usually the amount of manganese added is controlled between 0.1% - 0.5%.
Different alloying elements play different roles in cold rolled non-oriented silicon steel and have complex effects on its electromagnetic properties. In the production process of silicon steel, it is necessary to accurately control the addition amount of silicon, aluminum, manganese and other alloying elements. By optimizing the ratio of alloying elements, cold rolled non-oriented silicon steel can be maximized while ensuring good processing performance. Electromagnetic properties to meet the needs of many electrical equipment such as power transformers and motors for high-efficiency, low-loss magnetic materials, and promote energy conservation and development of the electrical industry.
