The temperature of the silicon steel sheet should not be too high or excessive during annealing. Excessively high will affect the insulating coating or bond the lamination. As for the general temperature of the silicon steel sheet, we will explain that the temperature of the oriented silicon steel sheet is about 800 degrees The annealing temperature of non-oriented silicon steel sheet is about 700 degrees, and the protective atmosphere in the furnace is strictly controlled to be non-oxidizing atmosphere during annealing.
It is based on the principle that the iron core punching sheet is not oxidized, carburized and the surface insulation coating of the electrical steel strip (silicon steel sheet) does not deteriorate significantly. It is best to choose a hydrogen-nitrogen mixed gas containing 2-10% of hydrogen. The addition of a small amount of hydrogen ensures that the iron core punches are not oxidized. The dew point in the protective gas should generally be below 0 ℃.