低熔点金属Fe对AlN-Mo复合陶瓷性能的影响

摘要

以氮化铝粉、钼粉为原料,采用放电等离子烧结(SPS)技术制备了AlN-18％Mo复合陶瓷.采用X射线衍射(X-ray diffraction,XRD)仪、扫描电镜(Scanning electron microscope,SEM)、介电频谱(Dielectric frequencyspectrum)分析研究了低熔点金属Fe对复合陶瓷导电性能及介电性能的影响.结果表明,随着低熔点金属Fe含量的增加,复合陶瓷的渗流转变温度逐渐降低,添加1％(体积分数)Fe,AlN-18％(体积分数)Mo复合陶瓷的渗流转变温度降低了90℃；随着低熔点金属Fe含量的增加,AM18复合陶瓷的介电常数、损耗逐渐增加,并从复合材料的显微结构及介电理论方面对以上结果给予解释.%The AlN-18%Mo composite ceramics were produced by spark plasma sintering (SPS) with A1N and Mo powders. The effect of low melting point iron on electric conduction and dielectric properties of the composite ceramics were studied by X-ray diffraction (XRD), scanning electron microscope (SEM), dielectric frequency spectrum. The results indicate that the addition of iron, which has low melting point, can decrease percolation transition temperature. With 1vol% Fe content, the percolation transition temperature of AlN-18vol5/oMo composite ceramics decreased by 90 °C. With the continued increasing the cotent of low melting point iron, the dielectric constant and loss of the composite ceramics were increased, the above results were explained by the microstructure of composite materials and the dielectric theory.