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　　摘要 以工业氧化铝溶胶为原料，通过溶胶-凝胶法制备了a-A12O3纳米粉体。研究了解胶条件、晶种加入量、矿化剂种类及加入量、煅烧温度及保温时间对产物的影响。结果表明：溶胶解胶后的粒度越小，产物的粒度越小，得到产物所需的煅烧温度越低；晶种和矿化剂的引入，可以促进过渡型氧化铝向a—A12O3的转化，降低相转变温度；煅烧温度对aA12O3的生成影响比较大，在温度恒定时，延长保温时间对产物物相的影响不大。溶胶-凝胶法制备a-A12O3纳米粉体的最佳条件是分散剂三乙醇胺用量为1％(质量分数),晶种加入量为5％，NH4NO3加入量为5％，煅烧温度为1000oC，保温时间为2 h。所得a-A12O3纳米粉体外观呈球形，粒度分布均匀，粒径在50 nm左右。(金刚石与磨料磨具工程2009年第一期)
　　
　　Abstract The a-A12O3 nanopowder was prepared by sol-gel method with industrial pure alumina sol as starting material．The effects of peptization condition，addition of seed crystal，addition and kinds of additives，calcination temperature and holding time on the crystal grain size of nano- A12O3 were investigated．The results show that the smaller the particle size after peptization is，the smaller the particle size of product is，and the lower the calcination temperature is．The addition of seed crystal and additive can accelerate the transition alumina changing to a-A12O3，and reduce the phase transformation temperature．The calcination temperature greatly influence the formation of a-A12O3，whereas the holding time has little effect on the phase of product．The spheric granules a-A12O3 nanopowders with 50 nm particle size and with even size distribution are obtained under the optimum condition of 1 wt％triethanolamine，5 wt％seed crystal，5 wt％NH4 NO3addition，1000 oC for calcination temperature and 2 h holding time．