Abstract
A series of high temperature radar wave-absorbing materials, SiCN/Si3N4ceramics, were prepared by hot-pressing. The nanometer SiCN powder, used as an absorber in the SiCN/Si3N4ceramic, was synthesized through laser pyrolysis of ((CH3)3Si)2NH) and NH3. The dielectric and mechanical properties of the prepared ceramics were investigated. XRD and SAED were conducted to study the growth of crystals in the ceramics. The results showed that the transformation of Si3N4from α to β was inhibited. The growth of the rod-like β -Si3N4grains in SiCN/Si3N4ceramics was retarded during hot-pressing process due to the existence of the nanometer SiCN particles. The relative density and the strength of the composites both decreased with the increase of the SiCN content in the composites. The dielectric properties of the ceramics prepared at different temperatures were very different. For the samples sintered at 1600∘C and 1700∘C, both the real and imaginary parts of the complex permittivity of them increased as the content of SCN powder in the sample obviously. For the sample with same concentration of SCN, the real and imaginary parts of them varied with the sintering temperature. SAED pattern revealed that structure of the SiCN in SiCN/Si3N4sintered at 1800∘C tended to crystallize fully. Its real, imaginary parts and dissipation factor were much lower than those sintered at 1600∘C and 1700∘C greatly.
Similar content being viewed by others
References
E. Mouchon, P.H. Colmban, J. Mater. Sci., 31, 323 (1996).
L. Tian, J. Mater. Sci., 33, 797 (1998).
H. Jiao, W. Zhou, and F. Luo, Fuhe Cailiao Xuebao/Acta Materiae Compositae Sinica, 20(4), 34 (2003).
D. Zhao and W. Zhou, Physica E: Low-Dimensional Systems and Nanostructures, 9(4), 679 (2001).
F. Luo, W. Zhou, D. Zhao, and H. Jiao, Airosp. mater. & Technol., 1, 8 (2002).
H. Musal, J. Hahn, and G. Bush, J. Appl. Phys., 63(8), 3678 (1988).
Author information
Authors and Affiliations
Corresponding author
Additional information
Supported by national natural science foundation of China (No. 50572090)
Rights and permissions
About this article
Cite this article
Fa, L., Mei, Z.D., Hua, Z. et al. Dielectric and mechanical properties of hot-pressed SiCN/Si3N4composites. J Electroceram 17, 83–86 (2006). https://doi.org/10.1007/s10832-006-9942-9
Issue Date:
DOI: https://doi.org/10.1007/s10832-006-9942-9