纳米α-Al_2O_3超细磨料绿色制备工艺的研究

Study on Green Preparation of Nano-sized Alumina Powders

本文研究了以Al(NO3)3·9H2O和NH3·H2O溶液为原料,以聚乙二醇为分散剂,并通过在溶胶-凝胶过程中加入高纯氧化铝晶种和引入AlF3添加剂制备工艺在较低温度下合成了纳米α型氧化铝。通过X射线衍射分析和差热分析,研究了由凝胶至α-Al2O3粉末的转变温度、物相和晶粒度。结果表明:该工艺可显著降低过渡型氧化铝向α型氧化铝的相转变温度,所制氢氧化铝凝胶经950℃锻烧可获得平均粒径为45nm的α型纳米氧化铝。由于该工艺显著降低了相转变温度,可节约大量能源,是一种环境友好的绿色合成工业。

Alpha alumina nanocrystabline powders,with mean particle size smaller than 45nm,were prepared by a novel green synthesis process using Al（NO3）3·9H2O and NH3·H2O solutions as raw materials, polyethylene glycol as disporsant . The process mainly profited from a seed-effect of fine grains and using AlF3 as additives. The transformation process from the gelata to the alpha aluminiuma powders were investigated by means of X-ray diffraction analysis and differential thermal analysis. The resuits show that the process can reduce dramatically the phase transformation temperature by using a seed and AlF3 additive. It was found that the gel could be completely transformed into α-Al2O3 at 950℃. It was verified that this process is a green and energysaving technique for preparing nanoseale powders.