采用柠檬酸溶胶−凝胶法制备铜锌掺杂Z型锶钴铁氧体Sr3(CuZn)xCo2(1−x)Fe24O41(x=0.1,0.2,0.3,0.4,0.5)样品。采用X线衍射(XRD)和扫描电镜(SEM)对样品的晶体结构、表面形貌进行表征。分别用圆柱体法和PPMS-9T型物性测量系统测量样品的室温电阻率和磁滞回线。用微波矢量网络分析仪测试该样品在2~18 GHz微波频率范围的复介电常数、复磁导率，并根据测量数据计算电磁损耗角正切和微波反射率，探讨该材料的微波吸收性能与电磁损耗机理。研究结果表明：所制备的样品呈六角片状形貌，晶体结构为Z型，呈软磁特性，其电阻率在半导体的电阻率范围内；当x=0.3、厚度为2.5 mm时，样品在频率为11.4 GHz时的最大吸收峰为29 dB，10 dB带宽对应频率为7.7 GHz，是一种宽带微波吸收材料；样品的微波吸收来自磁损耗和介电损耗，但以磁损耗为主。%The samples of CuZn-doped Z-type strontium ferrite Sr3(CuZn)xCo2(1−x)Fe24O41(x=0.1, 0.2, 0.3, 0.4, 0.5) were prepared by citric acid sol-gel process. The crystal structure and surface morphology of the particles were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The electric resistivity and the hysteresis loop of samples at room temperature were determined by cylinder method and PPMS-9T type physical property measurement system(PPMS), respectively. Their complex dielectric constant and complex permeability were measured by microwave vector network analyzer in the frequency range from 2 to 18 GHz, the reflection coefficient and loss tangent were calculated according to measurements, the microwave absorbing properties and the electromagletic loss mechanism of samples were studied. The results show that there samples have a Z-type hexaferrite crystal structure, a micro-hexagonal flaky powder morphology, a soft magnetic propertie and a resistivity in the semiconductor range. Sr3(CuZn)xCo2(1−x)Fe24O41 is a kind of microwave absorption material with wide band, an absorption peak is 29 dB at 11.4 GHz and a bandwidth above 10 dB is 7.7 GHz when its thickness is 2.5 mm andx=0.3. The microwave absorption of the samples results from both dielectric loss and magnetic loss but the latter is more remarkable.
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