用电弧等离子体制备超细AlN粉末的研究

A STUDY ON THE TECHNIQUE OF PREPARING ULTRAFINE AlN POWDER BY ARC PLASMA

介绍了利用直流电弧等离子体制备超细AlN粉末的方法。实验结果表明,在N_2-Ar气氛中制备的超细粉末是Al和AlN混合物,而在N_2-NH_3气氛中能制备出高纯度的超细AlN粉末。X射线衍射分析证明,在适当分压比的N_2-NH_3混合气体中所制出的超细AlN粉末不存在Al(即其氮化率达到100％),所得AlN粒子的最大几率直径为5.29nm,几何平均直径为21.0nm。本文最后对电弧等离子体的作用,AlN超细颗粒的生成机理及影响超细粉末中AlN含量的主要因素作了分析。

This paper persentes the method of preparation of ultrafine AIN powder by D.G arc plasma.Two kinds of AlN Powders were produced respectively in two diffcrent mixed gases, N_2-Ar and N_2-NH_3, by the nitridation reaction of the aluminium metal vapor evaporated by means of D.C arc plasma. The experimental results have shown that the Powder prepared in N_2-Ar gas always a mixture of Al and AlN powders, while in the N_2-NH_3 gas a pure ultrafine AlN Powder can be produced. By means of X-ray diffraction analysis, it was shown that the ultafine AlN powder produced in the N_2-NH_3 gas with a appropriate mix ratio of N_2 and NH_3 has no Al powder, i.e., the nitridation ratio of alu minium is 100%.The most probable diameter and the mean diameter measured by electronmicroscope are 5.29nm and 21.0nm respectively. In the last paragraph of this paper the actions of arc plasma, the mechanism of generating ultrafine AlN particles and the factors exerting an influence on the AlN content in the powder have been discussed.