摘要
β-Sialon based composites were successfully prepared from fly ash and carbon black under nitrogen atmosphere by carbothermal reduction-nitridation process. Effects of heating temperature and raw materials composition on synthesis process were investigated, and the formation process of the composites was also discussed. The phase composition and microstructure of the composites were characterized by X-ray diffraction and scanning electronic microscopy. The results show that increasing heating temperature or mass ratio of carbon black to fly ash can promote the formation of β-Sialon. The β-Sialon based composites can be synthesized at 1723 K for 6 h while heating the sample with mass ratio of carbon black to fly ash of 0.56. The as-received β-Sialon in the composites exists as granular with an average particle size of 2-3 μm. The preparation process of β-Sialon based composites includes the formation of O′-Sialon, X-Sialon and β-Sialon as well as the conversion processes of O′-Sialon and X-Sialon to β-Sialon.
以粉煤灰和炭黑为原料,采用碳热还原氮化法成功制备出β-Sialon基复合材料。研究了加热温度和配料组成对合成过程的影响,分析了材料的生成过程。采用XRD和SEM手段表征了合成材料的相组成和显微结构。结果表明：升高加热温度,增大炭黑与粉煤灰的质量比均可以促进β-Sialon的生成;将炭黑与粉煤灰质量比为0.56的试样加热至1723K并保温6h,可以合成β-Sialon基复合材料;合成材料中β-Sialon多以粒状形式存在,平均粒径为2~3μm;β-Sialon基复合材料的生成过程包括O′-Sialon、X-Sialon和β-Sialon的生成及O′-Sialon和X-Sialon向β-Sialon的转化过程。
基金
Project (51074038) supported by the National Natural Science Foundation of China
Project (N100302002) supported by the Fundamental Research Funds for the Central Universities, China
