界面对纳米SiC/LAS陶瓷复合材料微波介电性能的影响  

Effect of Interface on the Permittivity of Nanometer SiC/LAS Ceramic Composite

作　　者：罗发[1] 周万城[1] 赵东林[1] 焦桓[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《西北工业大学学报》2003年第2期123-126,共4页Journal of Northwestern Polytechnical University

基　　金：教育部博士点基金 (19990 6 99);航空科学基金 (99G5 30 82 )

摘　　要：利用激光诱导法制备的纳米 Si C和 LAS玻璃粉米 ,采用热压法制备纳米 Si C/ LAS陶瓷复合材料 ,研究了纳米 Si C/ LAS陶瓷复合材料微波介电性能与纳米 Si C含量、烧结温度以及碳界面层的关系。结果表明 ,在 1 0 80℃以下烧结温度对陶瓷致密度的影响较大而对陶瓷复介电常数的影响较小 ;但在 1 0 80℃以上烧结温度对烧结致密度的影响较小 ,而对陶瓷复介电常数的影响较大 ,复合材料复介电常数的实测值与计算值之间存在很大的差异。通过计算和分析认为 ,复合材料制备过程中纳米尺度的 Si C促进了碳界面层形成 。One item in the contract we signed is to study the effect of interface on permittivity of nanometer SiC/LAS ceramic composite. Subsection 2.3 presents the main results of our research. Subsubsection 2.3.1 gives the experimentally determined effect of different nano SiC contents——3, 5, 7, 10 wt%——on permittivity of nanometer SiC/LAS ceramic composite; the sintering pressure was 15 MPa and the sintering temperature for 30 min was 1 080℃; Fig.2 gives the variations of ε′ (real part) and ε' (imaginary part )of permittivity with nano SiC content. Subsubsection 2.3.2 gives the experimentally determined effect of different sintering temperatures——1 000℃, 1 080℃, 1 150℃ for 30 min——on permittivity and density after sintering of nanometer SiC/LAS ceramic composite; the nano SiC content was approximately 5wt%; Fig. 3 shows the variations of density after sintering, ε′ and ε' with sintering temperature. Fig. 4 gives variations of ε′ and ε' with nano SiC content computed with Polder Van Santen formula. Computed results in Fig. 4 differ much from experimental results in Fig. 2. Subsubsection 2.3.3 discusses the cause for this big discrepancy; this discrepancy is very likely due to the high permittivity of the carbon rich interface; the higher activity and the higher specific surface area of nano SiC facilitate the interface formation and intensify its influence on the permittivity of the SiC/LAS composite.

关 键 词：陶瓷复合材料 纳米SIC LAS玻璃陶瓷 复介电常数 碳界面层 

分 类 号：TQ129[化学工程—无机化工]