以高岭土制备β-sialon粉料

PREPARATION OF β-SIALON POWDER FROM KAOLIN

在高岭土和碳的混合物中,加入适量氧化铁作催化剂,在N_2气氛下,通过还原-氮化反应,制得β-sialon粉料。用X射线衍射法测定了在反应温度下生成物的相组成及相对含量的变化,并用化学分析方法测定了β-sialon粉料中的氮含量。用TEM观察了粉末合成前后的形貌。在此基础上,讨论了β-sialon形成过程。研究结果表明,β-sialon粉料中氮含量及Z值大小与工艺参数有关。

β-sialon powder was synthesized by adding ferrous oxide as a catalyzer in the mixture of kaolin and carbon black through carbothermal reduction-nitridation reaction. The phase composition and nitrogen content of products in the reaction were analysed using X-ray diffraction and chemical method respectively. It is shown that the forma-tion of β-sialon powder is affected significantly by the reaction conditions, including beating tomperature, holding time and the ratio of kaolin and C in the mixture. The morphology of the synthesized β-sialon was observed by TEM. The formation process of β-sialon is also discussed in detail.