Hebei Messi Biology Co., Ltd. stated that high-performance magnesium oxide with specific reactivity, particle size and flow characteristics can be used to manufacture transformer silicon steel sheets with grain orientation. During annealing, the steel is treated with a magnesium oxide coating to form a glass-ceramic film (forsterite). The insulating properties of this film are very important, as is the choice of different magnesium oxide grades.
The surface quality of grain-oriented silicon steel mainly depends on the formation quality of the magnesium silicate bottom layer. In normal production, defects such as dew crystals, black bottom layer, redness, bluishness, and color difference often occur in the bottom layer of magnesium silicate. In order to improve the quality of the bottom layer, this article The effect of magnesium oxide activity, magnesium oxide coating process, and decarburization time on the formation of the bottom layer of magnesium silicate was studied.
The results showed that the higher the activity of magnesium oxide, the better the formation of the bottom layer; the moisture content of the magnesium oxide coating should be controlled at a certain level. Within the range, if the moisture content is too low, it will cause dew crystal defects; the extension of decarburization time is conducive to the formation of the bottom layer of magnesium silicate.
A method for controlling the temperature of an oriented silicon steel magnesium oxide coating solution belongs to the technical field of metallurgy. The control method is carried out in a magnesia coating system composed of a liquid distribution tank and a circulation tank, wherein the liquid temperature of each liquid distribution tank and the liquid temperature of each circulation tank are controlled by a refrigerator, and the temperature between the refrigerator and each circulation tank is controlled by a refrigerator. There is a first temperature regulating valve on the pipeline connected to the liquid distribution tank, and a second temperature regulating valve is installed on the pipeline connecting the refrigerator and each circulation tank. Turn on the refrigerator and set the temperature to -10~0°C. Open the first temperature regulating valve and adjust the opening of the valve to 20-80% to control the liquid temperature in the dosing tank to 0-15°C, open the second temperature regulating valve and adjust the opening of the valve to 20-100% to control the circulating irrigation The temperature of the inner liquid is 5~20°C until the surface coating of the oriented silicon steel is finished. The control method designed in the present invention realizes the control of the moisture content of the magnesium oxide coating solution to a certain extent.