Silicon steel sheet is essentially an extremely low carbon steel plate with a mass fraction of 0.5%~5% of silicon. According to the use, silicon steel sheet can be divided into motor silicon steel sheet (the mass fraction of silicon is usually below 2.5%, the thickness is generally 0.5ram) and transformer silicon steel sheet (the mass fraction of silicon is usually 2.5% ~ 4.5%, the thickness is generally O.35mm); According to the production method, it can be divided into hot-rolled silicon steel sheet and cold-rolled silicon steel sheet, and cold-rolled silicon steel sheet can be divided into oriented silicon steel sheet (used to make transformers) and non-oriented silicon steel sheet (used to manufacture motors) according to different grain orientation.