燃烧合成法制备TiB_2-Al_2O_3复相陶瓷的组织结构及形成过程分析

Research on the fabrication of TiB_2-Al_2O_3 composites by self-propagating high temperature synthesis

采用自蔓延燃烧合成法在室温下的空气中制备出了TiB2-Al2O3复相陶瓷，通过X射线衍射（XRD）和扫描电镜（SEM）分析表明，合成的产物纯净，无中间相，TiB2的形貌为规则的块状，晶粒细小，平均尺寸为（2～5μm），弥散的分布在晶粒较大的Al2O3（40—50μm）四周，而Al2O3的形状不是很规则，该反应不同于一般的元素直接合成，而是由熔化-还原-化合组成的三步反应过程构成。

TiB2-Al2O3 composites were produced by Self - propagating High Temperature Synthesis. The final product was analyzed by means of XRD and SEM. The results showed that the product was pure, and no interphases appeared. The particles of TiB2 produced by reaction were fine with diameters of 2 - 5 um, and TiB2 with regular rectangle shape dispersed mainly in Al2O3 matrix. The size of Al2O3 was 40 -50um, and its shape was not regular. The reaction was different from general element direct synthesis, and was composed of melting,reduction and combination three steps.