表面析晶对熔融石英微波介电性能的影响  

Effects of surface crystallization on the microwave dielectric properties of fused silica

作　　者：张文宇[1] 郑勇[1] 程鹏[1] 吕学鹏[1] 董作为[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院,江苏南京210016

出　　处：《电子元件与材料》2014年第6期34-37,41,共5页Electronic Components And Materials

基　　金：国家自然科学基金资助项目(No.51174118)

摘　　要：采用传统固相烧结法制备了熔融石英微波介质材料,研究了表面析晶对材料物相组成、表面形貌及微波介电性能的影响。结果表明:材料从1 250℃开始析出方石英,且其析出量随烧结温度的升高而增多。当烧结温度低于1 300℃时,方石英析出量较少,表面析晶对材料微波介电性能影响不大,其介电性能主要随体积密度的增加而提高;而烧结温度超过1 300℃后,方石英析出量显著增加,引起材料内应力增大,使其表层裂纹加深甚至剥落,导致材料性能下降。经1 300℃烧结3 h所制材料具有最佳的微波介电性能。Microwave dielectric materials of fused silica were prepared by the conventional solid-state reaction method The effects of surface crystallization on the phase composition, surface morphology and microwave dielectric properties of samples were investigated. The results reveal that the initial precipitated temperature of cristobalite is 1 250 ℃ and the content of cristobalite increases with the increasing of sintering temperature. When the sintering temperature is lower than 1 300 ℃, there is only a small amount of cristobalite precipitation; surface crystallization has little influences on the microwave dielectric properties, which are mainly improved with the increase of volume density. While the sintering temperature exceeds 1 300 ℃, the amount of cristobalite increases noticeably, which makes the internal stress increased, surface crack deepened or even peeled off, thereby leading to the degradation of microwave dielectric properties. The fused silica sintered at 1 300 ℃ for 3 h exhibits the best microwave dielectric properties.

关 键 词：熔融石英 表面析晶 微波介质材料 方石英 烧结温度 微波介电性能 

分 类 号：TM28[一般工业技术—材料科学与工程]