Supply silicon B50A250 Application Notes

Silicon, the English name is silicon steel sheets, which is a very low carbon content of the soft magnetic alloy ferrosilicon, silicon content is generally 0.5 to 4.5%. Added silicon can enhance iron resistivity and maximum permeability, reduce the coercive force, core loss (iron loss) and magnetic aging. Silicon steel production due to process complexity, process windows narrow, difficult to produce, as the iron and steel products, arts and crafts, especially oriented silicon steel. Mainly used to produce various core transformers, motors and generators. World silicon steel production accounts for about 1% of the total (see precision alloy). Performance requirements for silicon performance requirements mainly are: ① low iron loss, which is the most important indicator of the quality of silicon. States are divided into grades according to iron loss and iron loss lower the higher grades. ② strong magnetic induction intensity magnetic field (magnetic induction) high, which makes the core size and weight reduction of the motor and transformer, saving silicon, copper wire and insulation materials. ③ surface is smooth, flat and uniform thickness, core fill factor can be improved. ④ punching good, the manufacture of micro, small motors more important. ⑤ adhesion and weldability surface of the insulating film is good, it can corrosion and improving punching property. ⑥ almost no magnetic aging. Typical magnetic properties shown in Table silicon silicon content generally increases with increased iron loss, reduce punching and magnetic induction, the hardness increased (Figure 3). The higher operating frequency, the greater the eddy current losses, the choice of silicon should be thinner. Rolled silicon steel smelting primary smelting with oxygen (also available EAF), with the vacuum treatment of molten steel and AOD technology (see refining, the use of molding or casting method. Depending on the use, change smelting silicon (0.5 ~ 4.5%) and aluminum (0.2-0.5%) content to meet the requirements of different magnetic silicon and aluminum content of a corresponding increase in high-grade silicon. minimize carbon, sulfur and inclusions magnetic, surface quality cold-rolled silicon steel sheet, fill factor and punching better than hot-rolled silicon steel sheet, and roll production, so from the beginning of the 1960s, some countries have stopped the production of hot-rolled silicon steel. China uses about 900 ℃ low temperature first into a pile of hot and fast hydrogen protection manufacture of hot-rolled steel sheet annealing method, the finished product rate is high, the quality of the finished product and the magnetic surfaces are better. rolled silicon steel hot rolled and cold rolled into two processes, conventional direct production of hot-rolled silicon steel finished craft now rarely used, mainly for hot and cold rolled to produce two processes, called cold-rolled silicon steel products. Depending on the product, is divided into multi-stand cold rolling mill single rack rolling and rolling, in which the single stand rolling oriented silicon steel products mainly produced cold rolled non-oriented cold-rolled non-oriented silicon steel slab or billet is hot rolled to a thickness of about 2.3mm coil. When low manufacturing silicon products, hot-rolled and cold rolled coil pickling to 0.5mm thick when manufacturing high-silicon products, hot-rolled strip after pickling (or the first by 800 ~ 850 ℃ after the normalization of pickled), cold rolled to a 0.55 or 0.37mm thick, hydrogen and nitrogen mixed atmosphere in continuous furnace 850 ℃ annealing, then by 6 to 10% smaller reduction ratio to 0.50 or 0.35mm thick cold-rolled cold-rolled reduction rate make this small grain growth during annealing, the iron loss is reduced. Both are cold-rolled sheet at 20% of hydrogen and nitrogen mixed atmosphere continuous furnace 850 ℃ final annealing and then coated with phosphate plus chromate insulating film grain oriented silicon steel generally contains Si3%, requires low levels of oxide inclusions in steel, and must contain C0.03 ~ 0.05% and the inhibitor (second phase dispersed particles or grain boundary segregation elements). Inhibitors that prevent primary recrystallization grain growth and promote the development of secondary recrystallization, thereby obtaining a high (110) [001] orientation. inhibitor itself harmful magnetic, so after the completion of inhibition, subject to purification annealing temperature when using a second phase inhibitors, slab heating temperature must be raised to make the original coarse second phase particles solution, followed by hot rolling or normalizing and then to fine particle precipitation, in order to enhance the inhibition of cold rolled finished thickness of 0.28,0.30 or 0.35mm, process points in Table 3. The cold rolled grain oriented silicon steel sheet with a thickness of 0.30 or 0.35mm oriented silicon steel strip, and then made by pickling, cold rolling and annealing