摘要
采用干凝胶法,以聚碳硅烷（PCS）为原料,通过炉内成球技术制备了SiC空心陶瓷微球。并利用TG、IR、SEM、XRD等方法对陶瓷微球进行了成键结构、表面形貌等分析,讨论了有机聚合物的陶瓷化过程机理。结果表明,干凝胶成球技术能利用经纯化处理的聚碳硅烷在500~600℃下得到SiC空心陶瓷微球,采用乙醇作为发泡剂可使PCS凝胶粒子得到良好发泡效果,提高载气中氦气含量至50%~80%可提高干凝胶粒子在吸热阶段的升温速率,微球经辐照后在850℃下碳化生成以β-SiC为主要相结构的球壳,球壳具有较好的表面平整度。
SiC ceramic microspheres were fabricated by drop-tower technique at low temperature using polycarbosilane（PCS）as raw material.The as-prepared microspheres were characterized by TG,IR,SEM and XRD.The reaction mechanism of organic polymer and the effects of process parameters（composition of furnace atmosphere and temperature）were investigated.The results show that ethanol as a blowing agent has a high blowing efficiency,and the content of helium gas in the furnace atmosphere ranging rising to 50%-80% can increase the heating-up rate of gel particles in heat-absorbing stage.The high sphericity morphology is obtained at 500-600 ℃.Moreover,the SEM spectra indicate that irradiation can increase the surface finish quality and evenness of hollow SiC ceramic microspheres.
出处
《原子能科学技术》
EI
CAS
CSCD
北大核心
2014年第4期757-762,共6页
Atomic Energy Science and Technology
基金
中国工程物理研究院科学技术发展基金资助项目(2013B0302053)
关键词
SIC
空心微球
聚碳硅烷
炉内成球法
SiC
hollow microsphere
polycarbosilane
drop-tower technique
