In order to study the edge quality of the hotrolled plate of oriented silicon steel is coarse, which readily leads to cracking during subsequent cold rolling, the thermal strength thermoplastic curve of oriented silicon steel and the thermal simulation test under various deformation conditions is measured by a thermal simulation testing machine. 
At 700 ℃ to 750 ℃, the reduction of area drops to the lowest point (approximately 35 %), and the fracture morphology shows fewer dimples, indicating brittle fracture, making it unsuitable for rolling within this temperature range. Additionally, due to the high internal distortion energy after hightemperature deformation, the deformed grains can be eliminated through static recrystallization, and the recrystallization grains grow.By reducing the roughing pass to 1+3, setting the edge heater at 90 ℃, strictly controlling the input of scaling water and cooling water in the rolling line to compensate the temperature drop at the edge of the oriented silicon steel, and using the side pressure of the vertical roll of the rough rolling 30mm to improve the degree of recrystallization at the edge,and reducing the loading gap of the oriented silicon steel to 50mm during the furnace loading,shortening the heating time of oriented silicon steel to 180 min can improve the edge quality of oriented silicon steel hot-rolled coil. The results showed that the edge quality excellence rate of oriented silicon steel hot-rolled coil is increased from approximately 30 % to more than 80 % after the process optimization, and there is no significant impact on the magnetic properties of the finished coil.

Effect of inner cover pressure and heating rate of car-type furnace on high temperature annealing quality of grain-oriented silicon steel was studied. The results showed that the inner cover pressure affected the quality of forsterite film by controlling water vapor discharge. Moderate pressure was conducive to the formation of uniform and continuous forsterite film, while too large or too small pressure caused forsterite film to be thin, and even appeared bare crystal phenomenon. The change of the position of the inner cover caused the difference in the heating rate of oriented silicon steel, which affected the magnetic property. The heating rate of the inner cover in the middle area of the car-type furnace was conducive to optimize the magnetic property, while the heating rate of the inner cover near the furnace door or the furnace wall leaded to the decrease of the magnetic property.

The effect of ambient temperature on oriented electrical steel was studied by testing the mechanical properties of ordinary oriented electrical steel hot rolled plate at 20~200 ℃ and combining the fracture morphology and metallographic organization observation. The results showed that: the mechanical properties of oriented electrical steel are sensitive to the ambient temperature, in the range of testing temperature, the strength decreases with the increase of temperature, in the range of 20~150 ℃, the strength decreases rapidly with the increase of ambient temperature, in 150~ 200 ℃, the strength decreases slowly; maximum force elongation and elongation after fracture increase with the ambient temperature in the range of 20~150 ℃, and in the range of 150~200 ℃, the strength decreases with the temperature. Between 150~200 ℃, it decreases instead with the increase of temperature, the maximum force total elongation is the highest at 150 ℃, and the post-break elongation is the highest at 100~150 ℃

Microstructure, texture and magnetic properties of cold rolling and annealing non-oriented silicon steel for high efficiency motor with normalizing and without normalizing were investigated through scanning electron microscope, EBSD and Epstein frame. The results showed that after normalizing, the cold rolling samples are featured by shear bands and deformation bands. Comparing to the samples without normalizing, the grain size of the samples with normalizing after annealing is bigger, the γ and α* fiber texture are weakened, while the ηfiber texture is enhanced. The iron loss of the samples with normalizing after annealing is lower and the magnetic induction intensity is higher.

Combined with the systematic pilot test research and electron backscatter diffraction (EBSD) detection means, the influence of "composition, microstructure and texture" of 2.7 %~3.6 % Si -0.5 %~2.0 %  Al -0.3 %~0.9 % Mn non-oriented silicon steel on the iron loss was investigated, and the main influencing factors were clarified. SPSS software was used to carry out the primary and secondary statistical analysis on the correlation of the factors affecting iron loss. On this basis, the multiple linear regression method and LightGBM algorithm were used to establish the prediction model of non-oriented silicon steel loss, and the fitting ability of the model was evaluated by the mean square error and average error of the prediction results. The results showed that: the textures of finished sheets are dominated by {111}〈112〉 and {114}〈481〉.The increase of Si, Al and Mn content increases the resistivity of nonoriented silicon steel, and the iron loss P_1.5/50 decreases accordingly.With the increase of grain size of the finished sheets, the iron loss P_1.5/50 decreases significantly.There are twenty-three main factors affecting the loss of nonoriented silicon steel by "compositionmicrostructuretexture".The mean square error of iron loss prediction model established by multiple linear regression method and LightGBM algorithm can reach 8.76×10^-3 and 3.81×10^-5, respectively, and the average error rate can reach 3.231 % and 0.210 %, respectively. The models established by the two methods can be used to predict the iron loss of non-oriented silicon. However, the prediction accuracy of the LightGBM algorithm is higher than that of the multiple linear regression model, and the interpretation of the prediction results of the multiple linear regression model is higher than that of the LightGBM algorithm.

The loss characteristics under medium frequency work conditions of two silicon steel materials were analyzed, the effect of frequency, temperature on loss property was studied, and application feasibility of two silicon steel materials in large capacity medium frequency transformers. 0.15  mm thin-gauge oriented silicon steel has lower loss below 400 Hz, while 0.08 mm ultra-thin grain-oriented silicon steel has lower loss above 400 Hz.The iron loss of both silicon steel materials under 60-130 ℃ complex conditions were decreased. The higher the temperature and the longer the heating time, the loss gradually decreases and finally reaches a stable state. Just from performance perspective, when the frequency ≤400 Hz, 0.15 mm thin-gauge grain-oriented silicon steel was more suitable for preparing large capacity medium frequency transformer cores, when the frequency ＞400 Hz, 0.08 mm ultra-thin grain-oriented silicon steel was more suitable for preparing large capacity medium frequency transformer cores.

The variation of manganese during BOF smelting was studied, the factors and the variation rules of end-point manganese content of liquid steel were analyzed. In view of actual production data in 220 t converter, the process route and operation methods for stably producing the steel containing manganese with the mass fraction of less than 0.10 % were obtained. By optimizing the gun position and carbon pulling time during the converter blowing process, controlling the endpoint oxidation and temperature of the converter, adopting a slag retention dual slag mode, and controlling the manganese content of the molten iron and scrap steel, as well as the amount of slag discharged from the steelmaking process, the residual manganese at the endpoint of the converter steelmaking is less than 0.07 %, which can meet the composition requirements of low manganese steel.

During the pouring process of aluminum-free and non-oriented silicon steel, the liquid level fluctuation range of the mold reaches ±10 mm, which seriously affects the quality of the slab and the production of the slab. The thermal conductivity, bulk modulus and elongation of aluminum-free steel were analyzed by high-temperature mechanical simulation and tensile test, and the proportion of austenite precipitation in the slab condensation temperature range of 1 080~1 250 ℃ was 44 %. The bulging belly of the billet in the fan-shaped section is the main reason for the fluctuation of the liquid level of the mold during continuous casting. By reducing the tundish temperature, accurately controlling the refining components, and optimizing the flow rate of the secondary cold water, the proportion of the liquid level fluctuation≤±3 mm of the mold was increased from 58.6 % to 99.5 %.

During the production of thin and high-grade NGO products on a certain silicon steel annealing coating line, there is a phenomenon of blackening on the surface of the strip. After analyzing the annealing furnace production conditions,and product appearance, this article takes measures to improve the airtightness of the annealing furnace and optimize the process system. Combined with actual production adjustments and optimizations, it reduces the oxidation on the surface of high-grade non oriented silicon steel strip, thereby reducing the blackening phenomenon on the surface of the strip.