中文摘要：

采用燃烧合成法,以硅粉和炭黑为原料,铝粉为掺杂剂,聚四氟乙烯为助燃剂,分别在不同坯体压力下制备成坯体,在0.1MPa的氮气气氛中合成Al掺杂β-SiC粉体。通过X射线衍射、扫描电镜和电子能谱对合成粉体的物相、微观结构及形貌进行了表征。同时在8.2～12.4GHz频率范围内进行了介电性能测试。结果表明随着坯体压力的增大,合成β-SiC粉体的晶格参数随之减小,且其介电性能随之降低。对合成机理和Al掺杂对SiC介电性能的影响进行了讨论。

英文摘要：

The Al doped SiC powders have been prepared by combustion synthesis in 0.1MPa nitrogen atmosphere under different body pressure,using silicon（Si） and carbon black（C） powders as raw materials,aluminum（Al） as doping source and polytetrafluoroethylene（PTFE） as additive.The prepared powders have been characterized by X-ray diffraction（XRD）,scanning electron microscope（SEM） and energy dispersive spectra（EDS）.The microwave dielectric property of prepared powders has been measured in the frequency range of 8.2-12.4GHz.Results show the lattice parameter and dielectric property of prepared powders decrease with body pressure increasing.The synthesized mechanism and effect of Al doping on dielectric property of SiC powder have been discussed.