摘要
采用添加成孔剂和冰冻-干燥法制备了具有不同气孔率的氮化硅多孔陶瓷,研究了该陶瓷在9.3GHz的微波介电性能。用SEM对微观形貌进行观察。结果表明,不同的成型工艺制备出具有不用孔结构的氮化硅多孔陶瓷,添加成孔剂制备的多孔陶瓷为较大的孔、洞分布在较致密的基体上;冰冻-干燥法制备的多孔陶瓷具有复合孔结构。对试样介电特性的研究表明,除了气孔率对介电常数和介电损耗有较大影响外,孔结构也是影响其介电特性的重要因素。
Two different series of porous silicon nitride ceramics, whose volume fractions of porosity are from 0 to 0.6, were fabricated using two different preparation routes： （i） the addition of pore-forming agent, and （ii） freeze-drying processing. Effects of the amount of pore-forming agent and the concentration of water-based slurry on porosity were investigated. In order to predict and understand experimental dielectric properties-porosity relationships, porosity, porous structure and dielectric properties were evaluated separately for each series of materials. The results showed that besides the volume fraction porosity, the geometrical nature was also a major factor that influences the dielectric properties of the samples.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2007年第A01期557-559,共3页
Rare Metal Materials and Engineering
基金
国家自然科学基金资助项目(90305016)
关键词
氮化硅
多孔陶瓷
成孔剂
冰冻
干燥法
介电性能
silicon nitride
porous ceramics
pore-forming agent
freeze-drying processing
dielectric properties
