中文摘要：

要采用固相反应合成法，以硅粉和炭黑为原料，分别在0．1MPa的氩气和氮气气氛中合成β-sic粉体。通过X射线衍射和扫描电镜对合成粉体的物相、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，在氩气中合成β-sic粉体其晶格参数小于在氮气中合成粉体的晶格参数，两者均小于标准值，但介电参数表现出了相反的趋势。讨论了合成机理和气氛对SiC介电性能的影响。

英文摘要：

The β-SiC powders were prepared by solid state reaction in 0. 1MPa nitrogen and argon atmos- phere, using silicon（Si） and carbon black（C） powders as raw materials. The prepared powders were characterized by X-ray diffraction（XRD） and scanning electron microscope（SEM）. The microwave dielectric property of prepared powders were measured in the frequency range of 8. 2 - 12. 4GHz. Results show that the lattice parameter of prepared powders in argon atmosphere is less than that of prepared powders in nitrogen atmosphere, both of which are less than the standard value of β-SiC. However, the dielectric property shows that the adverse trend due to the more defects generated in argon atmosphere. The synthesized mechanism and effect of atmosphere on dielectric property of SiC powder are discussed.