FeSiAl Magnetic Powder Core Prepared By Scrip Cast And Magnetic Core Application

Metal powder cores are produced by powder metallurgy method, and that are softmagnetic materials though a special process to obtain good comprehensive performance. Itis widely used in the field of Inductive components, inductance filter, switching powdersupply, transformer, and so on. They operating frequency can apply from Hertz toMegahertz.In the new century, with the advancement of technology, the development offunctional electronic devices, the metal powder core material put forward higherrequirements. FeSiAl magnetic powder core has a broad market prospect is widely used inhigh frequency because of its high resistance, low magnetic core loss, and low price.In this study, the scrip cast was applied to prepared FeSiAl powder, and studied theinfluence of size ration, insulating coating, pressing, heat treatment and other processfactors on the magnetic core performance.1. Using different scrip cast process to obtain FeSiAl sheet, and researching theinfluence of scrip cast process parameters on the scrip cast sheet structure. Experimentalresults using the roll speed of6m/s～8m/s, the pressure spray package of2.2×104Pa～2.7×104Pa to obtain sheet almost no adhesive tape phenomenon. The sheet about0.1mm~0.2mm thickness,3cm~7㎝long and2cm wide.By scanning electron microscopy and XRD photo analysis, the roll speeds higher theFeSiAl sheet grains has more fine and uniform. Comparing the FeSiAl powder coreprepared by scrip cast and prepared by ingot cast. The results show the FeSiAl powder coreprepared by scrip cast is more conducive to the insulating coating, has a smaller grain size,higher saturation magnetization and high permeability and lower loss.2. Experimental study the effect of single particle size on magnetic permeability andcore loss. Results show that large particle is easy to obtain high permeability and loss. Inorder to obtain the FeSiAl magnetic powder core have high permeability and low loss, the optimum particle size ratio of FeSiAl magnetic powder is2%of-40~+100mesh,11%of-100~+200mesh,40%of-200~+270mesh,10%of-270~+325mesh,37%of-325mesh.3. The insulation coating process is crucial. The result show that, to add mica andbinder good is a way to improve the frequency characteristics of magnetic core, reducingthe magnetic core loss, but also reduces the permeability. When mica content is0.6%,binder content is3.0%, the performance is best.4. Molding pressure is the basis for good magnetic powder cores and mechanicalproperties. and increasing the molding pressure is equivalent increased the density ofmagnetic core. The best compaction pressing is1200MPa.5. Annealing treatment is mainly to release internal stress and improve the strength ofmagnetic core. As the heat treatment temperature increasing, the permeability increasedand the loss reduction. When temperature higher than220℃, the permeability began toreduce and the loss increased. The best annealing treatment temperature is220℃.6. Magnetic Pretreatment can effectively improve the performance of magneticpowder cores and magnetic heat treatment is better than ordinary heat treatment.