作　　者： (袁振侠）; (陆有军）; (陈炜晔）; (吴澜尔）;

机构地区： 北方民族大学材料科学与工程学院,银川750021

出　　处： 《无机材料学报》 2017年第9期991-996,共6页

摘　　要： 以TiO_2和纳米炭黑为原料,机械干法混合后,在Ar气氛下微波碳热合成纳米TiC。合成产物通过XRD和SEM进行表征,研究了TiO_2粒径、反应温度、保温时间对微波碳热合成纳米TiC物相、显微形貌和TiO_2自身转化率的影响。实验结果表明,微波碳热还原合成纳米TiC经1300℃保温40 min和1400℃保温30 min可使TiO_2充分反应,且粒径为40 nm的TiO_2的转化率可达到98.2%,合成的TiC粒度分布均匀,平均粒径约小于100 nm。此外,根据固相扩散机制对不同反应温度下两种粒径TiO_2转化率随时间的变化进行了Avrami方程拟合,并绘制了两种粒径TiO_2的转化曲线,为TiO_2与纳米炭黑微波合成纳米TiC提供理论参考。 TiC powders were prepared via microwave carbothermic reduction in Ar with TiO2 and nano-carbon black as starting materials. Effects of TiO2 particle sizes, temperature and holding time on phase compositions, particle morphologies and TiC yields in the reaction products were investigated by means of X-ray diffraction （XRD） and scanning electron microscopy （SEM）. Avrami equation was fitted to the change of TiO2 conversion with time at different temperatures. Results show that TiO2 powders with average diameters ranging from 40 to 400 nm were fully reduced at 1300-1400℃ for 30-40 min with TiC yield as high as 98.2%. TiC powder with uniform particle size less than 100 nm was obtained in case of reaction at 1400℃ for 30 min by using 40 nm TiO2 as starting material. Transformation curves of TiO2 were prepared for the synthesis of nano-TiC by microwave carbothermic reduction.

关 键 词： 纳米 微波合成 物相分析 扩散机制