摘要
采用溶胶-凝胶法制备La1-xSrxMn1-yFeyO3（x=0．15，0．20，0．23；y=0．10，0．12，0．14，0．16），用HP8722型微波网络矢量分析仪测定样品在频率2-18GHz的电磁波吸收特性。发现Sr和Fe含量的改变都会影响体系的吸波性能，经测试得到x=0．2，y=0．14时的吸波特性最好。对于La1-xSr0.2Mn0.86Fe0.14O3，在涂层厚度为2mm时，有两个吸收峰，最大峰值达到了37dB，10dB以上的带宽达到了6．2GHz，在2-12．5GHz频率段微波吸收主要以介电损耗为主，在12．5GHz附近介电损耗和磁损耗发生突变，在12．5-18GHz频率段微波主要以磁损耗为主，电阻率在室温时处在半导体范围内，对吸波有利。
The experiment samples of La1-xSrxMn1-yFeyO3
（x =0. 15, 0.20, 0.23; y = 0. 10,0. 12, 0. 14, 0. 16） were prepared by sol-gel process, and the loss tangent and absorption coefficient in the range of 2 - 18 GHz were measured by HP8722 net analyzing apparatus. It is found that changing the content of Sr or Fe would effect the microwave absorbing. When the thickness of La1-xSrxMn1-yFeyO3 is 2 mm and x = 0.20, y = 0.14, the capability of microwave absorbing is the best one. There are peaks; maximum is 34 dB and two absorption effective band width with 10 dB and more reaches 6.2 GHz. When the frequency between 2 - 12.5 GHz dielectric loss is considered as the major loss from the loss angle picture. When the frequency gets to near 12.5 GHz the loss angle tangent increases or decreases suddenly. When the frequency between 12.5 ~ 18 GHz magnetic loss is be considered as the major loss. The resistivity of La0.8Sr0.2Mn0.86Fe0.14O3 at room temperature presents its semiconductor character, which is more beneficial to absorbing microwave.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2006年第3期314-317,共4页
Journal of the Chinese Society of Rare Earths
基金
湖南省科技计划资助项目(04FJ3034)
关键词
吸波材料
磁损耗
介电损耗
稀土
microwave absorbing materials
magnetic loss
dielectric loss
rare earths
