超约B_4C粉末的直流电弧法制备及扫描电镜研究

PREPARATION AND SEM STUDY OF SUPERFINE TETRA-BORON CARBIDE

以填B4C固体粉末（粒径约1mm）的高纯石墨棒为阳极，以高纯石墨捧为阴极，在He气氛下，用直流电弧法制备出了超细B4C的粉末，扫描电镜（SEM）研究表明，该超细B4C粉末的形状有三种：球及合有空洞的球、树枝状的棒或管、细小的颗粒，这些球及颗粒的粒径分布在数十纳米到数十微米范围内．这为粉碎莫氏硬度为9.28的B4C固体找到了新的、简便、可行的方法．

Superfine tetra-boron carbide has been prepared by DC are vaporizing method forthe first time. Through SEM study,it has been found that the superfine tetra-boron carbideprepared in this way has three kinds of forms -balls closed or opened,sticks or tubes like thetwigs of trees and normal particles. The particle diameters of the superfinp tetra-boron carbiddistribute from tens nanometres to micrometres. It has been found that Lne DC are vaporizingis a good way to grind the very hard B4C solid.