摘要
充分利用天然矿物钛铁矿(FeTiO3)中的铁和钛,采用反应烧结技术,成功制备了Al2O3TiC/Fe陶瓷复合材料。在真空热压炉中实现了合成与烧结一体化,为陶瓷复合材料的低成本制备进行了有益的探索研究。对钛铁矿Al C系统的热力学过程进行了详细的理论分析。研究表明:系统主要发生铝热还原反应,中间产物为多种钛的氧化物,系统反应后热力学上最为稳定的物质为Al2O3,TiC和Fe;系统反应最高温度低于Al2O3的熔化温度。通过实验研究,分析了产物的物相、结构和性能。反应烧结的最终产物主要为TiC,Al2O3和Fe。此外,还有少量Fe Al相,大部分为Al2O3。TiC晶体颗粒尺寸约为3~5μm,分布较为均匀,Fe分布于Al2O3,TiC晶粒之间。Y2O3和Cr2O3添加剂可以提高复合材料的抗弯强度。
An Al2O3-TiC/Fe ceramic composite was successfully prepared by a reaction sintering technique, using mineral ilmenite containing iron and titanium elements as the raw material. A preparation technique at a lower cost for synthesis and sintering of the advanced Al2O3- TiC/Fe ceramic composite was explored by heat press sintering in a vacuum hot-pressing furnace. The reaction thermodynamics of an FeTiO3- Al- C system were studied in detail through thermal analysis. The experimental results show that the process of synthesis starts from the melting of aluminum to an aluminothermic-reducing reaction, and proceeds to the formation of intermediary products of many kinds of titanium oxides, and the final and most stable products of thermodynamics after reaction sintering are TiC, Al2O3 and Fe. The maximum reaction temperature of the system is lower than the melting temperature of Al2O3 The composition, microstructure and properties of the products were also investigated. The results show that the composites con＇sist of TiC, Al2O3, Fe - binder and a few composites consist of Fe- Al. The average grain size is about 3 to 5 t^m, with even distribution. The Fe element is distributed between Al2O3 and TiC. The addition of Y2O3 and Cr2O3 can enhance the bending strength of the composites.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2005年第9期1173-1178,共6页
Journal of The Chinese Ceramic Society
基金
广西自然科学基金(桂科自0007021)
广西教育厅重点基金(桂教科研200322)
广西新世纪十百千人才工程基金(2002210)资助项目
关键词
钛铁矿
反应烧结
热力学
陶瓷复合材料
ilmenite
reaction sintering
thermodynamics
ceramic composite
