摘要
利用Al-TiO2-C体系熔铸法制备原位自生Al2O3-TiCP/Al基复合材料。采用Kissinger法测定该体系的激活能。该材料反应的动力学机制由熔化、扩散、反应和冷却四个阶段组成。该体系的主体反应为Al与TiO2之间发生的、伴随着强烈放热的置换反应,以及石墨粒子与其周围富钛层的反应。前者导致了Al2O3粒子生成;后者则生成了TiC粒子。基于理论计算和实验研究,建立了Al-TiO2-C体系MC合成工艺制备原位自生Al2O3-TiCP/Al基复合材料的动力学模型。动力学分析表明,石墨和TiO2颗粒愈细,混粉效果愈好,增强相的体积分数愈高,反应速率就愈大,反应完成所需时间也愈短。
The in situ Al2O3-TiCP/Al composites were successfully fabricated by melting and casting technique in Al- TiO2-C system. The free energies were determined by Kissinger method. The dynamic mechanism of the composite consisted of melting and diffusion and reaction and cooling stages. There were two main reactions. One was the displacement reaction between AI and TiO2 with releasing much heat; the other was the reaction between active Ti atoms with C powder. The former led to the formation of Al2O3 particles; the latter produced the formation of TiC particles. Based on the theoretical caleulation and experiment, the dynamic model of in situ Al2O3-TiCP/Al composites was established. The results show that the finer of TiO2 and C powders, the better the complex powder; the more reinforcements, the faster the reaction rate, and the shorter the reaction time.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2008年第5期770-774,共5页
Journal of Materials Science and Engineering
基金
国家教育部重点科学技术资助项目(206046)
黑龙江省博士后科研启动基金资助项目(LHK039)
