【摘要】 以溶胶-凝胶、碳热还原法制备了S IC/A L2O3纳米复相粉体,研究了处理温度对粉体相组成的影响及其在8.2~12.4 GH Z频率范围的介电性能。凝胶先驱体经1 700℃处理可得到S IC/A L2O3复相粉体,粉体为300~400 NM的球形颗粒,由晶粒尺寸约为45 NM的S IC和A L2O3纳米微晶组成;研究结果表明:A L原子未能固溶于S IC晶格中,导致随着粉体中A L含量的增加,复相粉体中A L2O3的量增加,粉体的复介电常数和介电损耗角正切降低。更多还原

【Abstract】 To the best of our knowledge,there is no paper in the open literature dealing with the preparation of SiC-Al₂O₃ nanocomposite powder with the method of sol-gel and carbonthermal reduction.We aim to explore preparing such nanocomposite powder with the above-mentioned procedure and then investigate the variation of its microwave permittivity with aluminum content in the frequency range of（8.2～12.4 GHz.） The powder synthesized at 1 700℃ in the atmosphere of argon consists of globose particles 300～400 nm in diameter,which,in their turn,consist of SiC and Al₂O₃ microcrystals approximately 45 nm in diameter.The atom of aluminum cannot resolve in the lattice of SiC;this induces both ε′,the real part of complex permittivity,and the dissipation factor tgδ to decrease with increasing aluminum content.tgδ denotes ε"/ε′,where ε" is the imaginary part of permittivity.更多还原