Transactions of Nonferrous Metals Society of China The Chinese Journal of Nonferrous Metals

您目前所在的位置:首页 - 期刊简介 - 详细页面

中国有色金属学报

ZHONGGUO YOUSEJINSHU XUEBAO

第22卷    第2期    总第155期    2012年2月

[PDF全文下载]        

    

文章编号:1004-0609(2012)02-0448-05
La1−xKxMnO3的微波吸收特性
黄生祥1,齐  伟1,周克省1,秦宪明2,陈  颖1,邓联文1,夏  辉1,韩建华1

(1. 中南大学 物理与电子学院,长沙 410083;
2. 厦门市宏业工程建设技术有限公司,厦门 361001
)

摘 要: 用溶胶−凝胶法制备La1xKxMnO3粉晶,用X射线衍射仪和扫描电镜表征样品的晶体结构和微观形貌,用微波矢量网络分析仪测试了该样品在2~18 GHz微波频率范围的复介电常数和复磁导率,并计算损耗角正切及微波反射率,分析K掺杂量和样品厚度对体系微波吸收性能的影响及微波损耗机制。结果表明:晶体结构为钙钛矿型,颗粒形貌为不规则椭球状或短棒状;当样品厚度为2.40 mm、x=0.3时,吸收峰值为27.1 dB,10 dB以上有效吸收频带宽度达10.6 GHz。纳米La1xKxMnO3兼具介电损耗和磁损耗,介电损耗相对较强。磁损耗因子和介电损耗因子随微波频率的变化相反,是基体中铁磁与反铁磁团簇在微波电磁场作用下相互转变引起。

 

关键字: La1−xKxMnO3;微波吸收;电磁损耗;钙钛矿

Microwave absorption properties of La1−xKxMnO3
HUANG Sheng-xiang1, QI Wei1, ZHOU Ke-sheng1, QIN Xian-ming2, CHEN Ying1,
DENG Lian-wen1, XIA Hui1, HAN Jian-hua

1. School of Physics and Electronics, Central South University, Changsha 410083, China;
2. Xiamen Hongye Project Build Technique Co., Ltd., Xiamen 361001, China

Abstract:The La1xKxMnO3 powders were prepared by so1-gel method. The crystal structure and surface morphologies of the particles were characterized by X-ray diffractometry and scanning electron microscopy, respectively. The complex dielectric constant and complex permeability were measured by microwave vector network analyzer in the frequency range from 2 to 18 GHz, and the reflection coefficient and loss tangent were calculated according to measurements. The results show that the crystal structure of La1xKxMnO3 is perovskite and its crystal powder morphology is irregular ellipsoidal shape or short rod, and the absorption peak is 27 dB and the bandwidth above 10 dB is 10.6 GHz when the thickness of the sample is 2.40 mm (x=0.3). Nano-La1xKxMnO3 has both dielectric loss and magnetic loss, but the former is relatively stronger. Due to the mutual transformation between ferromagnetic and antiferromagnetic clusters of the matrix in the microwave electromagnetic field, the magnetic and dielectric loss tangent changes inversely with the changes of microwave frequency.

 

Key words: La1−xKxMnO3; microwave absorption; electromagnetic loss; perovskite

ISSN 1004-0609
CN 43-1238/TG
CODEN: ZYJXFK

ISSN 1003-6326
CN 43-1239/TG
CODEN: TNMCEW

主管:中国科学技术协会 主办:中国有色金属学会 承办:中南大学
湘ICP备09001153号 版权所有:《中国有色金属学报》编辑部
------------------------------------------------------------------------------------------
地 址:湖南省长沙市岳麓山中南大学内 邮编:410083
电 话:0731-88876765,88877197,88830410   传真:0731-88877197   电子邮箱:f_ysxb@163.com