PREPARATION OF NANOSIZED SILICON NITRIDE POWDERS BY AMMONO SOL GEL PROCESSING
来源期刊：中国有色金属学报(英文版)1997年第3期
论文作者：Gao Jiming Xiao Hanning Zhang Li Du Haiqing
文章页码：22 - 25
Key words：silicon nitride； nanosized powder； ammonolysis； sol-gel
Abstract: Silicon nitride (Si 3N 4) powders were synthesized with silica sol, urea and carbon black by ammono sol gel processing. Urea was dissolved in water and mixed homogeneously with silica sol. Ammonoly sis of the aqueous solution could form a precursor, which was then mixed with carbon black and nitrided at1 300～1 600 ℃ under a flowing N 2 atmosphere. The precursor and final powder were characterized by X ray diffractometry, infrared spectroscopy and transmission electron microscopy. Results showed that Si 3N 4 powders with a size of 50～80nm and a content of more than 37% nitrogen can be obtained from the precursor annealed at 1 500 ℃ under a N 2 flow of 3 L/min for 2 h. Effects of ammonolysis and synthesizing conditions on the final products were investigated.
