摘要
以硅溶胶为硅源,蔗糖为碳源,采用低温碳热还原法合成了SiC微粉。低温处理过程为室温到800℃,升温速率为6℃/min。在低温处理过程中蔗糖-硅溶胶混合前驱体转化为球形碳颗粒和SiO2的混合物。800℃以上的升温速率为15℃/min。低温处理后的反应前驱体在1700℃下反应1h全部转化为β-SiC,产物的颗粒尺寸在1μm左右,为近似球形的颗粒。升高反应温度有利于提高反应速率,缩短反应时间。延长反应时间能增加转化率。
SiC powders were synthesized by reducing silica with saccharose in a flow argon atmosphere at 1500℃, 1600℃ and 1700℃, respectively. During the process of the pyrolysis of saccharose, the spherical carbon particles were obtained with the heating rate of 6℃/min from room temperature to 800℃. The reaction systems can be completely transformed into β-SiC at 1700℃ for 1h. The synthesized products are mainly composed of spherical β-SiC particles with the size of about lμm. The increased reaction temperature and extended holding time will greatly accelerate the reaction rate and increase the production of SiC.
出处
《硅酸盐通报》
CAS
CSCD
北大核心
2007年第6期1049-1052,共4页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金(50472094)
