成孔剂和硅粉粒度对反应烧结氮化硅性能的影响  

Effect of the Pore-Forming Agent and Silicon Powders Size on the Properties of RBSN

作　　者：徐洁[1] 罗发[1] 陈黄鹂[1] 李军奇[1] 苏晓磊[1] 周万城[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：《稀有金属材料与工程》2007年第A01期269-272,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(90305016)

摘　　要：以硅粉为原料,通过添加不同含量的成孔剂,反应烧结制备出具有不同气孔率的低密度多孔氮化硅陶瓷,研究了成孔剂含量和硅粉粒度对反应烧结氮化硅性能的影响。结果表明,随着成孔剂含量的增加,试样气孔率变大,强度随之减小,烧结后试样中的α-Si3N4相增多,介电常数实部和介电损耗降低,最低介电常数实部可达到2.4左右;不同粒度硅粉中添加30%(质量分数,下同)成孔剂的坯体烧结,在气孔率保持不变的条件下,初始硅粉粒度越小,烧结后试样强度越大,介电常数实部和介电损耗明显减小。The effect of the pore-forming agent content and silicon powders size on the dielectric and mechanical properties of RBSN ceramics were investigated. The experimental results demonstrate that the dielectric constant, the dielectric loss and the bending strength of the samples reduce in certain degree with porosity increasing. The minimum dielectric constant is about 2.4. The α-Si3N4 phase content rises with porosity increasing. The bending strength is improved with the decrease of silicon powders size, but the dielectric constant and the dielectric loss of the ceramics fall evidently.

关 键 词：反应烧结 成孔剂 硅粉粒度 介电常数 

分 类 号：TQ174.1[化学工程—陶瓷工业]