摘要
研究了不同粒度的Si3N4粉体对制备的逆反应烧结Si3N4-SiC复合材料性能的影响。结果表明:同一升温制度下,Si3N4粒度从0.074 mm减小到0.045 mm,Si3N4-SiC复合材料体积密度增大,显气孔率变低,抗折强度降低。随着Si3N4粒度减小,材料中的Si3N4含量降低;中温保温从900℃升到1200℃,Si3N4含量升高;高温保温温度从1350℃到1500℃,材料内部氧化程度增高,Si3N4含量降低,SiO2含量升高;Si3N4-SiC复合材料玻璃相增多,玻璃相中有SiO2晶体析出,使得孔隙被生成的玻璃相和发育的SiO2晶粒填充,材料的气孔减少。
The effects of Si3N4 granularities on the properties of Si3N4/SiC composites prepared by converse reaction sintering were investigated.The results showed that the bulk density of Si3N4/SiC composites increased,but the absorption and apparent porosity and the flexural strength decreased as the granularity of Si3N4 decreasing from 0.074 mm to 0.045 mm.Meanwhile,the content of Si3N4 in the compsites decreased.As the soaking temperature at the intermediate temperature increased from 900 ℃ to 1200 ℃,the content of Si3N4 increasing.As the soaking temperature at the high temperature increased from 1350 ℃ to 1500 ℃,the oxidation inside the material rose,the content of Si3N4 decreased,but the SiO2 congtent increased.The glass phase in Si3N4/SiC compound material increased.Some SiO2 crystal bled from the glass phase so that the pores were filled with the generated glass phase and SiO2 crystal grain produced from the glass phase,and the porosity of composites decreased.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2009年第S1期246-249,共4页
Journal of Synthetic Crystals
基金
国家自然科学基金(No.50672055)
国家科技支撑计划项目(2006BAF02A28)
关键词
逆反应烧结
粒度
SI3N4/SIC
converse reaction sintering
granularity
counter-reaction sintering
grain size
Si3N4/SiC
