低温烧结铁氧体/陶瓷复合材料的电磁性能研究

摘要

Two kinds of ferrite/ceramic composite materials:MgCuZn ferrite/CaTiO3 (MCZF/CT) and MgCuZn ferrite/BaTiO3 (MCZF/BT) have been prepared at 900 and 950℃ by standard ceramic technology to adapt to the low temperature co-fired ceramic (LTCC) technology.It can be found that the cut-off frequency of each material increases from 13.9MHz (MCZF) to 136.9MHz (MCZF/CT),and the dielectric loss at 1MHz decreases from 0.741 (MCZF) to 0.012 (MCZF/BT).When the sintered temperature increases from 900 to 950℃,the initial permeability,Snoek's product and permittivity of two composites increase,and the dielectric loss decreases.Among them,the initial permeability of MCZF/CT reaches 51.8,which was obviously higher than that of MCZF/BT,but the latter has relatively better frequency characteristics in dielectric properties.Furthermore,the electromagnetic properties of the composites sintered at 950℃ have been discussed combining with the analysis of microstructures.%采用MgCuZn铁氧体(MCZF)分别与少量CaTiO3(CT)和BaTiO3 (BT)复合,以Bi2O3为助熔剂,通过标准陶瓷工艺在900和950℃烧结得到适合低温共烧陶瓷(LTCC)工艺的两类复合材料MCZF/CT和MCZF/BT.对比研究铁氧体与两类复合材料的磁性能和介电性能发现,与陶瓷复合后材料的截止频率可以从13.9MHz提高到136.5MHz,而1MHz处的介电损耗可以从0.741降低到0.012.对比研究不同烧结温度下复合材料的电磁性能发现,950℃烧结的样品比900℃烧结时有更高的起始磁导率、Snoek产量、介电常数及更低的介电损耗,其中MCZF/CT的起始磁导率达到51.8,明显高于MCZF/BT,但后者有更优良的介电频率特性.此外,结合微结构分析讨论了950℃烧结样品的电磁性能变化原因.