AIN-SiC复相材料的制备及其微波衰减性能

PREPARATION AND MICROWAVE ATTENUATION PERFORMANCE OF AIN - SiC COMPOSITES

以氮化铝、碳化硅为原料,采用热压烧结工艺,1900～2000℃、氮气氛下,制备了AlN-SiC复相材料。运用XRD,高分辨率透射电子显微镜、网络分析仪等测试手段,研究了微波衰减剂碳化硅含量及AlN-SiC部分固溶体的形成对材料微波衰减性能的影响,结果表明:AlN-SiC复相材料的频谱特性随衰减剂碳化硅含量的变化而呈现出选频衰减、宽频衰减等特性。当衰减剂SiC质量分数少于40％时,AlN-SiC复合材料具有选频衰减特性,SiC含量为40％～60％时,复合材料具有宽频衰减特性。AlN-SiC部分固溶体的形成有助于改善材料的宽频衰减特性。

AlN-SiC composites were prepared by hot-pressing with AlN and β-SiC as the starting materials at the temperatures ranging from 1900 to 2000°C for 1 h in a nitrogen atmosphere. The effect of the microwave attenuator SiC content and the formation of the solid solution on the microwave attenuation performance of the AlN-SiC composites was studied by XRD, high resolution transmission electron microscopy and network analyzer. The results show that the frequency band attenuation performance is changed with the content of the attenuator SiC. There are narrow frequency band attenuation performances for AlN-SiC composites with lower mass fraction of SiC (<40%), while there are wide frequency band attenuation performances for AlN-SiC composites with the SiC content of 40%-60% (in mass). The formation of partial AlN-SiC solid solution is helpful to improve the wide frequency band attenuation performance of AlN-SiC composites.