MoO3添加对高频MnZn功率铁氧体性能的影响

Effects of MoO3 additive on the magnetic properties of MnZn high frequency power ferrites

采用陶瓷工艺制备高频MnZn功率铁氧体材料,研究了MoO3添加对材料微结构和磁性能的影响。用X射线衍射仪(XRD)、扫描电子显微镜(SEM)表征材料结构,用B-H分析仪测试材料磁性能,并对材料功率损耗进行分离。结果表明,适量添加MoO3可以有效改善材料的微观结构,提高致密度,提高材料饱和磁通密度和起始磁导率,降低功率损耗。功耗分离后发现,随着MoO3添加量的增加,磁滞损耗比例下降,涡流损耗所占比例上升。最佳MoO3添加量为0.01 wt%,获得低功耗的MnZn功率铁氧体,100℃、500kHz、50mT条件下功耗为86 kW/m3,起始磁导率约为1928,25℃下的饱和磁通密度为513 mT。

High-frequency MnZn ferrites were prepared by solid state reaction and the influence of MoO3 additive on the microstructure and magnetic properties were investigated.We examined the microstructure by XRD and SEM,the composition of powders by X-ray fluorescence analyzer,soft magnetic properties such as power losses(Pcv)and saturation magnetic flux density(Bs)by B-H analyzer.The results illustrate that proper addition of MoO3 is beneficial for microstructure optimized leading to high densification of bulk materials.Moreover,saturation magnetic flux density(Bs)and initial permeability(μi)are improved correspondingly,causing power losses decreased.After loss separation,it is found that the ratio of hysteresis loss(Ph)decreases and that of eddy current loss(Pe)increases when the content of MoO3 additive increases.The high-performance MnZn power ferrites are obtained with high Bs(513 mT),highμi(1928)and low power losses(86 kW/m3,500kHz-50mT-100℃)when the content of MoO3 additive is 0.01 wt%.