Fe/Al_2O_3复合材料的还原制备及其表征  

Reductive Preparation and Characterization of Fe/Al_2O_3 Composite

作　　者：孙凯[1] 张红梅[2] 范润华[1] 张子栋[1] 史志成[1] 高萌[1] 燕克兰[1] 李静[1] 

机构地区：[1]山东大学 材料液固结构演变与加工教育部重点实验室,山东济南250061 [2]中国重型汽车集团有限公司,山东济南250001

出　　处：《稀有金属材料与工程》2013年第S1期165-167,共3页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51172131);教育部新世纪优秀人才支持计划(NCET-10-0518)

摘　　要：金属陶瓷复合材料是由金属或合金与陶瓷相组成的非均质复合材料。由于金属和陶瓷的电导率、磁导率具有较大的差异,金属陶瓷复合材料表现出独特的电磁性能。以Al2O3和Fe2O3粉体为原料,通过高能球磨、无压烧结和选择性还原工艺,成功制备出不同组分的Fe/Al2O3复合材料,利用XRD、SEM对复合材料的物相组成及微观形貌进行分析和观察。结果表明:还原后样品的主晶相为(FexAl1-x)2O3固溶体和Fe3O4,并且出现了亚微米级粒度的Fe颗粒。利用阻抗分析仪对样品的介电性能的研究(测试频率为10MHz～1GHz)表明,材料的介电常数实部和虚部均随着频率增加而下降,并且随着原料中Fe2O3含量的增加而呈上升的趋势,这种介电常数增大的现象主要由界面极化引起。Metal-ceramic composite is a non-homogeneous composite which consists of metals or alloys and ceramics. Due to the great different electrical conductivity and magnetic permeability between metals and ceramics, the metal-ceramic composites show unique electromagnetic properties. Fe2O3 and Al2O3 powders were used as raw materials and high energy ball milling, pressureless sintering and selective reduction were conducted to prepare different components Fe/Al2O3 composites. The microstructure and phase characterization of the bulk composite by were analyzed XRD and SEM. The results show that the main crystalline phases of the reductive samples are (Fe x Al 1-x )2O3 solid solution and Fe3O4 with submicron Fe particles. Then the dielectric properties were tested by the Impedance Analyzer(the test frequency is 10 MHz～1 GHz). The real part and the imaginary part of the dielectric constant of the samples both decrease with the increase of test frequency; however when the Fe2O3 content of raw material increases, they exhibit a rising trend. The phenomenon of increasing dielectric constant is mainly caused by the interfacial polarization.

关 键 词：金属陶瓷复合材料 选择性还原 介电常数 

分 类 号：TB333[一般工业技术—材料科学与工程]