ZnO含量对MnZn铁氧体频率特性和直流叠加特性的影响

Effect of ZnO content on the frequency dependence and DC superposition characteristics of MnZn ferrites

采用传统的陶瓷工艺制备MnZn功率铁氧体材料,研究了ZnO含量对材料频率特性和直流叠加特性的影响。结果表明:截止频率随ZnO含量的增加先降低后增高,磁导率越高,截止频率越低;高饱和磁感应强度是获得较好直流叠加性能的基础;随叠加直流的增大,ΔBs-r(=Bs-Br)逐渐增大,而后开始缓慢下降,ΔBs-r较大的样品,其直流叠加特性较好;磁导率随叠加直流的增大先增加后缓慢减小,最后趋于平缓。

MnZn power ferrites were prepared by conventional ceramic process. The effects of ZnO content on the frequency dependence and DC superposition characteristics of the ferrites were investigated. The results show that the cutoff frequency firstly decreases and then increases with increasing ZnO content. Higher permeability results in lower cutoff frequency. High saturation magnetic induction was a basis of obtaining good DC superposition characteristics. As the direct current increases, △Bs-r（=Bs-Br） first increases, and then decreases slowly. Better DC superposition characteristics results from higher △Bs-r. With increasing direct current the permeability firstly increases and then decreases slowly, tends to be gentle finally.