提纯土状石墨对铝碳材料显微结构和力学性能的影响  

Effect of Purified Amorphous Graphite on Microstructure and Mechanical Properties of Al_2O_3-C Refractories

作　　者：梁雄[1] 李亚伟[1] 张雨[1] 桑绍柏[1] 王庆虎[1] 

机构地区：[1]武汉科技大学,耐火材料与高温陶瓷国家重点实验室培育基地,武汉430081

出　　处：《硅酸盐学报》2014年第3期357-365,共9页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(51072143;51372176);武汉市科技攻关项目(2013010602010210)资助

摘　　要：采用高温碱煅烧法提纯土状石墨,并将其作为1种活性碳源,引入到含金属铝粉、硅粉和二氧化硅微粉的铝碳耐火材料中。利用热重--差示扫描量热仪、X射线衍射仪、扫描电子显微镜、能谱仪及三点弯曲仪等研究了提纯土状石墨对铝碳材料显微结构和力学性能的影响。结果表明:提纯土状石墨颗粒由许多细小的微晶片状石墨组成,尺寸细小,结构褶皱且绕曲变形;与天然鳞片石墨相比,提纯土状石墨的氧化活化能低,具有更高的反应活性;在铝碳材料中引入提纯土状石墨部分取代天然鳞片石墨,促进了材料基体内AlN和SiC晶须形成,对提高铝碳材料的力学性能有积极作用,在铝碳材料中有很好的应用前景。The amorphous graphite was purified by calcining under high temperature and alkali conditions, acting as a kind of reactivity carbon source, and then incorporated into Al2O3-C refractories containing tabular alumina, graphite flake, metallic a- luminum, silicon and microsilica power in this work. Microstructure and mechanical properties of Al2 O3-C refractories were in- vestigated by thermogravimetric analysis-differential scanning calorimetry, X-ray diffraction, scanning electron microscopy cou- pled with energy dispersive X-ray spectroscopy and three-point bending method. The result showed that the purified amorphous graphite, consisted of very small particles, was fold and sheet. Also, the oxidation activation energy of purified amorphous graphite was much lower than that of graphite flake, which indicated that purified amorphous graphite had higher reactivity. When purified amorphous graphite was incorporated into A12 O3-C refractories, its addition promoted the formation of A1N and SiC whiskers, and had a positive effect on improving mechanical properties of Ale O3-C refractories, indicating that purified a- morphous graphite has promising atmlication Drosneets in Al2Os-C refractories.

关 键 词：提纯土状石墨 氧化铝一碳耐火材料 反应活性 显微结构 力学性能 

分 类 号：TQ175[化学工程—硅酸盐工业]