Hebei Messi Biology Co., Ltd. stated that based on the first domestic silicon steel continuous annealing-coating experimental unit project developed by a steel plant, it conducted research and analysis on the selection of magnesium oxide for oriented silicon steel coating, developed a magnesium oxide coating system for oriented silicon steel, and studied the magnesium oxide coating process based on this coating system. The main contents are as follows:
(1) According to the coating mechanism and the characteristics of magnesium oxide, a method for selecting silicon steel grade magnesium oxide was proposed. The mechanism of action of magnesium oxide in oriented silicon steel production was analyzed, and a method for characterizing and testing the characteristics of silicon steel grade magnesium oxide was proposed. Through the characterization and detection of magnesium oxide and the comparison of microscopic morphological structure differences, the selection basis of silicon steel grade magnesium oxide was proposed.
(2) A magnesium oxide coating system for oriented silicon steel was developed. The factors affecting the coating thickness of magnesium oxide coating were analyzed, and this was used as the design principle of the magnesium oxide coating system. A coating system consisting of a coating machine, a drying and curing furnace, and a coiler was designed, and a coating thickness prediction and control method based on soft measurement was established.
(3) Research on magnesium oxide coating process for oriented silicon steel. The influence of the surface cleaning before annealing and the oxide layer formed during annealing on the bottom layer was analyzed. Through experimental research, the configuration of the coating liquid, the selection of additives, the drying and curing temperature, the coiling tension distribution and other processes were determined.
(4) Application and inspection of magnesium oxide coating process for oriented silicon steel. The coating effects of magnesium oxide coating and magnesium silicate bottom layer formed after high temperature annealing were tested respectively, and the magnesium silicate bottom layer formed under different coating amounts was compared, which verified that the appropriate magnesium oxide coating amount can not only improve the surface quality, but also help the final product to improve the magnetic induction and reduce the iron loss.