The tested grainoriented silicon steel was deformed at 30 % rolling reduction at 1 100 ℃ and 970 ℃ respectively, and was kept warm at rolling temperature. The influences of the rolling temperature and the holding time on the size distribution and volume fraction of inhibitor particles were observed by thermal field emission scanning electron microscopy. The precipitation amounts of Cu and Mn at the rolling surface,near surface and center of the grainoriented silicon steel under different processes were determined by inductively coupled plasma mass spectrometer. The results showed that the large size particles are the composite precipitates of CuS and MnS during the hot rolling process. The hot rolling temperature and holding time have no obvious impact on the precipitation of Mn-containing inhibitors. The lower the hot rolling temperature (970 ℃), the faster the precipitation of Copper-containing inhibitors is, but the holding time has no impact on the further precipitation of Copper-containing inhibitors, and inhibitors still remains in the precipitation state after deformation. With the extension of the holding time, the precipitation amount of copper-containing inhibitors increases after high temperature(1 100 ℃) thermal deformation/hot rolling.

Based on research of 0.27 mm gauge high magnetic induction grain oriented silicon steel, the influence of the laser scribing power, scribing frequency, scribing speed and scribing spacing on the core loss reduction and magnetic domain structure of grain oriented silicon steel were studied in this paper. It was showed that there were differences in the morphology and domain structure of the scribing lines in different processes. The scribing lines showed light morphology and the magnetic domains were inhomogeneous and scattered at low power, high frequency and high speed.The results showed that the maximum iron loss reducing rate reached 9.47 % under the parameters of 30 % scribing power, 50 kHz scribing frequency, 500 mm/s scribing speed and 5 mm scribing space. Besides that, under the interaction of laser scribing parameters, the iron loss reducing rate increased significantly with the increase of laser energy density, and the damage to the stress coating of grain oriented silicon steel aggravated with the increasing of energy density, which was not conducive to the magnetic domain refinement and the increase of iron loss reduction.

The evolutions of microstructure and texture of medium temperature Cu-bearing grain oriented silicon steel under hot rolling, first cold rolling, decarburizing annealing and second cold rolling were studied by EBSD technology. The results showed that the microstructure and texture of the hot rolled plate were uneven in the thickness direction, the surface layer was recrystallized grains, the center layer was mainly deformed grains, and the Goss grains were mainly distributed in the subsurface. The Goss grain was an unstable rolling texture, which will disappeared after the first and second cold rolling and reappeared after annealing, which reflected the genetic characteristics of Goss. After cold rolling, the texture gradually concentrated on α-line texture, and the higher the compression rate, the sharper the texture was. After annealing, the texture gradually migrated to γ texture.

The magnetic properties of the middle grade nonoriented silicon steel of  1.3 %-2.0 %  Si were improved under the same testing standard when the coiling temperature increased from  630 ℃  to  720 ℃ , but the black line defect were appeared on the steel’s surface after rolling.The main reason for this was that the increase of coiling temperature changed the structure of the strip surface, and too much residual iron oxide was appeared on the surface of the strip after pickling, which caused the black line defects on the surface of the strip after cold rolling.The practice proved that the black line defects on the rolled surface could be eliminated by means of rewinding and secondary pickling, which could improve the magnetic properties and ensure the surface quality.

The effects of different cleaning processes on cleaning quality of grain oriented silicon steel were studied. Different cleaning quality corresponded to different primary grain size and magnetic properties of final products. The results showed that the cleaning quality of steel plate surface was improved with the increase of cleaning solution concentration , cleaning temperature and cleaning time. The difference of cleaning quality would lead to the change of the primary grain uniformity of the steel plate. The primary grain of steel strip with better cleaning quality was even and the magnetic properties of the final products was good.

In this paper, ANSYS Maxwell and ANSYS Workbench software were used to simulate the performance of magnetic and mechanical properties of WISCO DW series non-oriented silicon steel. The electromagnetic simulation results showed that the high frequency core loss of  0.35  mm silicon steel sheet was  48.9 %  lower than  0.50  mm silicon steel, and the average efficiency of the motor could be improved by  0.8 % . It indicated that the use of thin gauge silicon steel could significantly reduce the core loss and improve the motor efficiency, while the silicon steel sheet with same thickness had little effect on the motor efficiency. The mechanical simulation results showed that the maximum stress of rotors with different thicknesses silicon steel concentrated on the magnetic bridge area of rotor and increased significantly with the speed. When the speed was greater than  12 000  r/min, the maximum stress was generally proportional to the speed by power  2.06 . At the same time, when the width of the magnetic bridge was less than  1.6  mm, the maximum stress value increased significantly with width gradually decreasing. To sum up, the use of thin gauge, high strength non oriented silicon steel can meet the development requirements of high efficiency and high speed of motors of new energy vehicle. This study can provide certain guidance for the research and development of non oriented silicon steel for new energy driving motor and the optimization design of motor structure.

Through the change of total oxygen content in the tundish during the ladle exchange moment and the composition analysis of slag in tundish, meanwhile combining with the effects of ladle slag carry-over in continuous casting and the defects of slab, the influence of ladle slag carryover in continuous casting was obtained. The results showed that ladle slag carry-over deteriorated the liquid steel castability, causing the blocking of SEN and the oxidation of alloy element and reducing the molten steel purity. In severe cases, it might cause serious results such as corrosion of SEN, solidified crust of tundish slag and so on. According to the characteristics of steel quality requirements, the development of differential ladle slag control process can effectively balance the product quality and the production costs.

Process control system is a kind of management and control system used in manufacturing enterprise shop floor. It connects the upper planning management system and the lower industrial control system, and optimizes the management of the entire production process through information transfer. In order to implement process control system in iron and steel enterprises, it’s necessary to design reasonable hardware and software architecture, and carry out appropriate system integration according to the production characteristics of process industry. The system plays an important role as the information center of iron and steel enterprises. The network architecture and software architecture of process control system in silicon steel department were introduced in this paper, of which the system integration technology was also analyzed and studied. 

The market scale,production and patent applications of grainoriented silicon steel of private enterprises in China in the past 10 years were researched. The results showed that the last decade was an important stage for the rapid development of  grainoriented silicon steel in  China's private enterprises. Great progresses of  grain-oriented silicon steel in these enterprises have been made in terms of production capacity, output and even the development of high-end products and the number of patents about grain-oriented silicon steel in these enterprises has increased year by year. But it could be found that the number and proportion of invention patents were still low, and the patents' quality was not high.The applicant with the largest number of patents was Baotou Weifeng New Materials Co., Ltd..