缺铁配方YCaZrIG铁氧体的结构及电磁性能研究

摘要

采用传统氧化物法制备了Y2.7Ca0.3Zr0.3Fe4.70-δO12(0≤δ≤0.15,YCaZrIG)石榴石型铁氧体,研究了烧结温度及缺铁量对铁氧体相组成、烧结性能、显微结构及电磁性能的影响.结果表明,制得的YCaZrIG铁氧体均为单相石榴石结构.缺铁越多,越难烧结.缺铁对介电常数影响不大,但可显著降低介电损耗.适量缺铁和提高烧结温度可促进铁氧体中晶粒生长.于1 475℃烧结的缺铁量δ=0.15的样品,结构致密,晶粒尺寸最大(15～20μm),综合性能最佳:介电常数εr=14.6,介电损耗tanδe=2.4×10-4,饱和磁化强度4gMs=187.9 mT,矫顽力Hc=37 A/m,剩磁B=85.8mT,共振线宽△H=5.09 kA/m.%Y2.7Ca0.3Zr0.3Fe4.70-δO12 (0≤δ≤0.15, YCaZrIG) ferrites were prepared by the conventional oxides method.The effects of sintering temperature and iron deficiency δ on the phase composition, sintering performance, microstructure and electromagnetic properties of YCaZrIG ferrites were investigated. All the prepared YCaZrIG ferrites are identified to be pure garnet phase. Iron deficiency shows little effect on the dielectric permittivity, but leads to reduction in the dielectric loss and increase in the sintering temperature. Appropriate iron deficiency and increasing sintering temperature promote the grain growth in YCaZrlG ferrite. The YCaZrlG ferrite with δ = 0.15 sintered at 1 475 ℃ possess the largest grain size of 15～20 μm and shows the optimum properties: εr=14.6, tanδe= 2.4×10-4, 4πMs= 187.9 mT, Hc= 37 A/m, Br= 85.8 mT, △H (resonance linewidth) = 5.09 kA/m.