亲疏水性SiO2复合有机树脂包覆对FeSiCr磁粉芯性能的影响

研究了亲疏水性SiO₂复合有机树脂对FeSiCr磁粉芯性能的影响以及退火热处理对磁粉芯磁性能的影响。将FeSiCr合金粉末经磷化处理后,分别采用疏水性、亲水性两种不同类型的SiO₂复合有机树脂对粉体进行绝缘包覆,经压制成型并固化制备成FeSiCr磁粉芯。结果表明,采用偶联改性亲水性SiO₂复合有机树脂的包覆效果明显优于疏水性SiO₂复合有机树脂包覆。随着SiO₂添加量的增加,磁粉芯的体电阻率和矫顽力增加,而密度、饱和磁化强度及磁导率降低;采用质量分数0.5%疏水性SiO₂复合有机树脂包覆工艺制备的FeSiCr磁粉芯退火后综合性能最优,在20 mT,100 kHz测试条件下,磁损耗仅为49.84 kW/m³,相比于采用纯树脂包覆工艺制备的磁粉芯损耗下降了16.9%。退火热处理能够有效提高FeSiCr磁粉芯的磁性能。

Effects of hydrophilic and hydrophobic SiO2 composite organic resin coating on properties of FeSiCr magnetic powder cores

The effects of hydrophilic and hydrophobic SiO₂ composite organic resin on the properties of FeSiCr magnetic powder cores and the effects of annealing treatment on magnetic properties were studied.After phosphating,the FeSiCr alloy powders were coated by two types of SiO₂ composite resin,which are hydrophobic and hydrophilic,respectively.The FeSiCr magnetic powder cores were prepared by compaction and curing.The results show that the coating effect of coupling modified hydrophilic SiO₂ composite organic resin is better than that of hydrophobic SiO₂ composite organic resin.With the increase of SiO₂ addition,the specific resistance and coercivity of the magnetic powder cores are increased,while the density,saturation magnetization and effective permeability are decreased.The FeSiCr magnetic powder cores coated with 0.5%hydrophobic SiO₂ composite organic resin have excellent comprehensive performance after annealing.Under the condition of 20 mT,100 kHz,the magnetic core loss is 49.84 kW/m 3,which is 16.9%lower than that of the magnetic powder cores coated with pure resin.Annealing can effectively promote magnetic properties of FeSiCr magnetic powder cores.