溶胶-凝胶法制备的Z型铁氧体Sr_3(NiZn)_xCo_(2(1-x))Fe_24O_41的微波吸收性能  

Microwave absorbing properties of Z-type hexaferrite Sr_3(NiZn)_xCo_(2(1-x))Fe_24O_41 prepared by sol-gel process

作　　者：周克省[1] 周丽芳[1] 邓联文[1] 黄生祥[1] 程静[1] 唐璐[1] 杨力妮 

机构地区：[1]中南大学物理与电子学院,长沙410083

出　　处：《粉末冶金材料科学与工程》2014年第3期486-492,共7页Materials Science and Engineering of Powder Metallurgy

基　　金：湖南省科技计划资助项目(2011SK3258);粉末冶金国家重点实验室开放基金资助项目(2011)

摘　　要：用溶胶-凝胶法制备镍锌共掺杂Z型锶钴铁氧体Sr3（NiZn）xCo2（1-x）Fe24O41（x=0～0.5）粉末。用X射线衍射（XRD）和扫描电镜（SEM）表征该铁氧体粉末的晶体结构和表面形貌，并测试其室温磁滞回线和室温电阻率。用微波矢量网络分析仪测定该粉末在2～18 GHz微波频率范围的复介电常数和复磁导率，根据测量数据计算电磁损耗角正切及微波反射率，分析该材料的微波吸收性能与电磁损耗机理。结果表明：Sr3（NiZn）xCo2（1-x）Fe24O41粉末呈六角片状形貌，晶体结构为Z型，具有良好的软磁特性；x=0.3时该材料的电阻率最低，微波吸收效果最好，在13.5 GHz频率的吸收峰为25.1 dB，10 dB频带宽度为7.7 GHz，兼具强的磁损耗和弱的介电损耗。Ni, Zn-doped Z-type strontium ferrite Sr3（NiZn）xCo2（1-x）Fe24O41（x=0, 0.1, 0.2, 0.3, 0.4, 0.5） powder were prepared by sol-gel process.The structure, particle morphology, room temperature hysteresis loops of powders were characterized by X-ray diffraction （XRD）, scanning electron microscope（SEM）and physical property measurement system（PPMS-9T）, respectively. The room temperature resistivity of samples was measured by cylinder method. The complex permittivity and the complex permeability of samples were measured by microwave vector network analyzer in the frequency range from 2 to 18 GHz. The microwave reflectance and loss tangent were calculated from measurements, and the microwave absorbing properties and the electromagnetic loss mechanism of samples were studied. The results show that Sr3（NiZn）xCo2（1-x）Fe24O41 has a Z-type hexaferrite crystal structure, a micro-hexagonal flaky powder morphology and a good soft magnetic propertiy. When its thickness is 2.4 mm and x=0.3, it has a lower resistivity and the strongest microwave absorption that an peak is 25.1 dB at 13.5GHz and a bandwidth above 10 dB reaches 7.7 GHz. The microwave absorption of samples results from magnetic loss mainly and dielectric loss weakly.

关 键 词：溶胶-凝胶法 Z型锶铁氧体 镍锌掺杂 微波吸收 电磁损耗 

分 类 号：TM25[一般工业技术—材料科学与工程] TB34[电气工程—电工理论与新技术]