| Magnetic powder cores is one of soft magnetic composites, which is manufactured by the conventional PM process, can be described as ferromagnetic powder particles surrounded by an electrical insulating film. Fe-Si-Al-Ni-Ti soft magnetic alloy powders were prepared by gas atomization, and subsequently magnetic powder core was obtained by compression molding of the powders. The morphology and phase composition of the alloy powders were analyzed by scanning electron microscopy and X-ray diffraction. The magnetic properties of the magnetic powder core were measured by soft magnetic alternating current measurement. The effects of powder size, type and content of insulation binder, and heat treatment process parameters on effective magnetic permeability, power loss and quality factor of powder core have been studied, respectively.In the paper, the influence between the annealing temperature, holding time and the powder of carbon content as well as the powder of oxygen were investigated. The results show that with the rise of annealing temperature and the extension of holding time, the powder of carbon and oxygen content decreased. When the temperature for850℃, time for1h, powder get the lowest carbon and oxygen content. At this time, Powder purity in the highest, and without aggregation phenomenon, beneficial to the fine magnetic powder core magnetic can be get.The influence between the particle size and particle size distribution and the effective permeability, power loss, quality factor of Fe-Si-Al-Ni-Ti soft magnetic cores were investigated. The results show that With the decrease of the particle size distribution, the effective permeability and power loss reduced, quality factor increased, and this time, comprehensive magnetic of cores get best.The influence between the Pressing force size and the effective permeability, power loss, quality factor of soft magnetic were investigated. When W-6C epoxy resin and silicon resin adding content is0.5%, The former magnetic powder cores has higher effective permeability, lower power loss. With the content of insulation binder increase, effective permeability and loss reduced, and the quality factor improved, at this time, core get the best frequency stability properties.The influence between the Pressing force size and the Pressure billet density, sample density, effective permeability of core were investigated. The results show that with the pressing force increased, the Pressure billet density and sample density of the cores has rose, and the effective permeability increased, too.The influence between the heat treatment temperature, heating rate, holding time and the Fe-Si-Al-Ni-Ti magnetic powder core performance influence were investigated. The results show that When the temperature increases from180℃to280℃, the effective magnetic permeability increases slightly and the loss decreases apparently. When the annealing temperature reaches380℃, the effective permeability decreases sharply and the loss increases apparently. When the heating rate increase, the effective permeability and quality factor are increase first and lower late, loss is reduce first and increase late, when the heating rate is120℃/h, magnetic powder cores get the best magnetic. With the extension of the time of heat, the effective permeability and quality factor increase constantly, and loss reduce constantly, when the holding time is150min, magnetic powder cores get the best magnetic.Finally, the influence between Ti elements and the magnetic property of Fe-Si-Al-Ni-Ti magnetic powder cores have been researched and analysed. The results show that the effective magnetic permeability, loss and quality factor along with the change of Ti content show different change rule. Along with the change of Ti elements, the μe rose first and reduce late, when the content of Ti elements is1%, magnetic powder cores get the best magnetic. With the increase of the content of Ti, loss has reduced. when the content of Ti elements is2%, magnetic powder core get the best magnetic. with the change of Ti, Pe and Ph of the cores Show totally different change rule, the two get the minimum value when the content of Ti are1%and2%. Along with the increase of the content of Ti, quality factor of the cores, reduce first and increased late. when the content of Ti elements is2%, it gets maximum value. This means that at this time the comprehensive magnetic of magnetic powder core can be best. |
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