自蔓延燃烧合成β-Si_3N_4棒晶  

Self-Propagating High Temperature Synthesis of β-Si_3N4 Rod-like Crystals

作　　者：陈殿营[1] 张宝林[1] 庄汉锐[1] 李文兰[1] 徐素英[1] 

机构地区：[1]中国科学院上海硅酸盐研究所,上海200050

出　　处：《无机材料学报》2002年第4期696-702,共7页Journal of Inorganic Materials

基　　金：中国科学院上海硅酸盐研究所创新基金资助项目

摘　　要：采用自蔓延高温合成（SHS）,在高压氮气中成功地合成了β-Si3N4棒晶,研究了添加不同量Y2O3对自蔓延燃烧合成β-Si3N4。棒晶长径比的影响.结果表明,Y2O3添加量有一个最佳范围,当Y2O3的添加量在2Wt％～5wt％时,棒晶生长均匀,长径比约为8.通过铜坩埚吸热淬火的方法,观察到β-Si3N4棒晶不同生长阶段的显微形貌,从而推测其生长机理为VLS和VS两种机理协同作用的结果.本文对β-Si3N4棒晶生长的反应历程也进行了阐述.β-Si3N4 rod-like crystals were fabricated under high pressure nitrogen by using the Self-propagating High-temperature Synthesis method. The effect of different amount of Y2O3 addition on the aspect ratio of β-Si3N4 rod-like crystals was studied. By using copper crucible to absorb the heat generated by the exothermic reaction to quench the reaction, the growth morphology of β-Si3N4 in the different stages of the reaction was observed. The reaction courses were also expounded. The results reveal that the optimum amount of Y2O3 addition is 2 wt%-5 wt%. Too much amount of Y2O3 addition could result in the inhomogeneous growth and distribution of the crystals. By considering the morphology of the products, the growth mechanisms of β-Si3N4 rod-like crystal are the results from the synergy of the VLS and VS.

关 键 词：自蔓延燃烧合成 Β-SI3N4 棒晶 生长机理 氮化硅陶瓷 

分 类 号：TQ174.758[化学工程—陶瓷工业]