稀有金属材料与工程
稀有金屬材料與工程
희유금속재료여공정
RARE METAL MATERIALS AND ENGINEERNG
2009年
12期
2089-2092
,共4页
翟晓勇%周万城%罗发%朱冬梅
翟曉勇%週萬城%囉髮%硃鼕梅
적효용%주만성%라발%주동매
短切SiC纤维%LAS玻璃陶瓷%介电性能
短切SiC纖維%LAS玻璃陶瓷%介電性能
단절SiC섬유%LAS파리도자%개전성능
chopping SiC_f%LAS glass-ceramic%dielectric properties
采用热压烧结法制备出致密的短切SiC_f增强LAS玻璃陶瓷复合材料,并讨论保温时间与热压压力对复合材料介电性能的影响.结果表明,测试频率在8~12 GHz之间,复合材料复介电常数实部ε′由基体的7.6上升到10~100,虚部ε″由基体的0.34上升到40~160,介电损耗tgδ由基体的0.04上升到1~20,并具有明显的频散效应.随保温时间的延长或热压压力的提高,复合材料ε′增大,ε″与tgδ减小.此外,断口形貌的SEM观察表明,随保温时间的延长或热压压力的提高,复合材料界面层变厚.
採用熱壓燒結法製備齣緻密的短切SiC_f增彊LAS玻璃陶瓷複閤材料,併討論保溫時間與熱壓壓力對複閤材料介電性能的影響.結果錶明,測試頻率在8~12 GHz之間,複閤材料複介電常數實部ε′由基體的7.6上升到10~100,虛部ε″由基體的0.34上升到40~160,介電損耗tgδ由基體的0.04上升到1~20,併具有明顯的頻散效應.隨保溫時間的延長或熱壓壓力的提高,複閤材料ε′增大,ε″與tgδ減小.此外,斷口形貌的SEM觀察錶明,隨保溫時間的延長或熱壓壓力的提高,複閤材料界麵層變厚.
채용열압소결법제비출치밀적단절SiC_f증강LAS파리도자복합재료,병토론보온시간여열압압력대복합재료개전성능적영향.결과표명,측시빈솔재8~12 GHz지간,복합재료복개전상수실부ε′유기체적7.6상승도10~100,허부ε″유기체적0.34상승도40~160,개전손모tgδ유기체적0.04상승도1~20,병구유명현적빈산효응.수보온시간적연장혹열압압력적제고,복합재료ε′증대,ε″여tgδ감소.차외,단구형모적SEM관찰표명,수보온시간적연장혹열압압력적제고,복합재료계면층변후.
The chopping SiC_f/LAS composites were prepared by the hot-pressing method. The effects of hot-pressing time and pressures on the microstructures and the dielectric properties of the composites were researched. Compared with the LAS matrix and the SiC fibre, the results of dielectric constant testing in the range of 8-12 GHz indicate that the dielectric constant real part, imaginary part and dielectric dissipation of all samples increase by 1-3 orders of magnitude, and show obvious frequency dispersion effect. Their real parts increase while their imaginary parts and dielectric dissipations decline with the increase of the hot-pressing time or pressures. The SEM fractographs show that the composite interfacial films between the fibre and the matrix are thickened with the increase of the hot-pressing time or pressures.