热处理温度对纳米晶Ba3(Zn0.4Co0.6)2Fe24O41晶相和X波段吸波特性的影响

采用溶胶-凝胶自蔓延法制备了Ba3(Zn0.4Co0.6)2Fe24O41铁氧体粉末,先将样品在450℃退火2h,然后将其分别在950、1100、1150、1200、1260℃下热处理5h。利用XRD和微波矢量网络分析仪对产物的晶体结构、X波段的电磁性质及其吸波性能进行了表征。实验表明,1200℃和1260℃热处理后的样品主相为六角Z相结构,并且在整个所测频段内都具有很大的磁导率虚部,后者还具有很高的磁导率实部;1mm厚的上述两样品在X波段内其反射功率损耗都在20dB以上,1200℃热处理后的样品反射功率损耗的最大值达43.112dB,上述两样品具有宽频大功率损耗特性,是X波段较为理想的微波吸收剂。

Effects of Annealing Temperature on Crystal Structure and Microwave Absorbing Properties in X Band for Nanocrystalline Ba3(Zn0.4Co0.6)2Fe24O41

Ba₃(Zn_0.4Co_0.6)₂Fe₂₄O₄₁ ferrite particles were prepared by sol-gel self-propagating combustion method,then sintered at 450℃ for 2 hours firstly,and then sintered at 950,1100,1150,1200 and 1260℃,respectively.The characterization studies by using such as X-ray diffractometry（XRD） and vector network analyzer have been carried out to explore the crystal structure,electromagnetic parameters and microwave absorbing properties in X band.It was discovered that the main phases of the samples sintered at 1200℃ and 1260℃ were hexagonal Z-type structure.The two samples provided with larger imaginary parts of the complex permeabilities,and the latter one also showed a bigger real part of that.For the two samples with 1mm thickness,the reflecting power losses in X band are all over 20dB,and the maximum of the reflecting power loss is 43.112dB for the 1200℃ annealed sample.It indicates that the two samples possess the broadband high-loss property,and they are a sort of very promising microwave absorption material in X band.