短切SiC_f/LAS复合材料的介电性能  

Dielectric Properties of Chopping SiC_f/LAS Composites

作　　者：翟晓勇[1] 周万城[1] 罗发[1] 朱冬梅[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,西安710072

出　　处：《材料导报》2009年第14期19-21,共3页Materials Reports

基　　金：国家自然科学基金资助项目(50572090)

摘　　要：讨论了纤维长度与热压保温时间对含量为25%(体积分数)的短切SiCf增强LAS玻璃陶瓷复合材料介电性能的影响。在8～12GHz频率范围内,介电性能测试结果表明,随纤维长度由2mm增加到4mm,复合材料的复介电常数实部ε′增大,而其虚部ε″及介电损耗tgδ减小。当保温时间由10min延长到20min时,复合材料的ε′增大,而其ε″与tgδ均减小;且保温20min时,其ε′、ε″与tgδ均已接近适合损耗微波能量的数值。复合材料有望成为电损耗型宽带微波损耗材料。The influences of the fibre length and hot-pressing time on the dielectric properties of the LAS glassceramic composites reinforced with 25vol% chopping SiC fibre are discussed. In a range of 8-12GHz, the measurement results of the dielectric constant indicate that the ε′of the composite samples sintered for 10minutes or 20minutes increases and their ε″ and tgδ decline with the increase of the fibre length from 2mm to 4mm. The ε′of the composite samples increases while their ε″ and tgδ decline with the increase of hot-pressing time from 10minutes to 20minutes, and the ε′ , ε″ and tgδ of the composite samples sintered for 20minutes approach the numerical value of microwave dissipation. It is shown that the chopping SiC4/LAS composites are provided with potential for broad band microwave dissipation.

关 键 词：复合材料 短切SiC纤维 LAS玻璃陶瓷 介电性能 

分 类 号：TB332[一般工业技术—材料科学与工程]