不同碳源和反应温度对原位合成SiC-TiC超细粉末的影响

以碳化硅(SiC)、二氧化钛(TiO2)和不同种类碳源为初始原料,采用碳热还原法在氩气气氛下原位合成SiC-TiC超细粉末.探讨了不同碳源和不同反应温度对所合成的SiC-TiC超细粉末的物相组成和显微形貌的影响.采用X-射线衍射仪(XRD)、激光粒度分析仪、扫描电镜(SEM)等手段对所合成的SiC-TiC超细粉末进行表征.实验结果表明,以蔗糖为碳源合成SiC-TiC超细粉末的适宜条件为1450 ℃保温2 h;以炭黑或葡萄糖为碳源合成超细粉末的适宜条件为1500 ℃保温2 h.三种碳源中以炭黑为碳源时所合成的SiC-TiC超细粉末粒度最小且合成出的粉末样品分散性好,大部分球状颗粒在0.5~1.0 μm 左右.在SiC粉末中原位合成的TiC颗粒,以粒径在0.1~0.2 μm左右的不规则的多样化结构颗粒存在.

Effect of Different Carbon Source and Reaction Temperature on In-situ Synthesis of SiC-TiC Ultrafine Powder

SiC-TiC ultrafine powder was synthesized by a carbothermal reduction method using SiC, TiO2 and different types of carbon source as raw materials.The effects of different carbon sources and calcination temperatures on the phase composition and microstructure of SiC-TiC ultrafine powder were discussed.The synthesized powders were characterized by X-ray diffraction (XRD), laser particle size analyzer and scanning electron microscope (SEM).The experimental results show that the suitable conditions for the preparation of SiC-TiC ultrafine powder with sucrose as carbon source is at 1450 ℃ for 2 h.The optimum condition for the preparation of SiC-TiC ultrafine powder with carbon black or glucose as carbon source is at 1500 ℃ for 2 h.SiC-TiC superfine powder possess the smallest particle size when carbon black is used as a carbon source in three kinds of carbon sources.The particles of SiC-TiC superfine powder are dispersive with particle size of 0.5-1.0 μm.In-situ synthesized TiC particles in SiC powders exist in irregularly diversified structure particles with particle sizes of 0.1-0.2 μm.