纳米α-Al_2O_3/W复合粉体的制备

Preparation of α-Al_2O_3/W Nanocomposite Powder

论述了非均相沉淀法制备纳米α—Al2O3/W复合粉体的实验过程,以及纳米钨粉对α—Al2O3相转变温度的影响.结果表明:纳米钨粉的存在降低了α—Al2O3的相转变温度.本实验所制凝胶在1000℃真空中煅烧1h可获得平均粒径<50nm的α—Al2O3/W粉体.

Al2O3/5vol%W and Al2O3/10vol%W nanocomposite powders, with mean particle size less than 50nm, were prepared by the heterogeneous precipitation process using A1(NO3)3 9H2O and (NH4)2CO3 solutions as raw materials and tungsten nanometer powders as additives in different ratios. α-Al2O3/W nanocomposite was obtained by calcining A1(OH)3/W dried gel at 1000℃ for 1h in vacuum. Adding tungsten nanometer powders can reduce the phase transformation temperature to alpha alumina. The composite powder is simply mechanically mixed together, alumina coating is on the surfaces of nanometer tungsten powder.