Ⅰ绪言钨粉的平均粒度测定广泛地使用着Fisher公司的Sub—Sieve—Sizer(以下略记为F—SSS)方法。规定其用法的ASTM和Fisher公司的说明书指出:以横座标为孔隙度,绘出孔隙度和粒度的关系曲线,采用曲线为水平或孔隙度为最小时的粒度为费氏 INTRODUCTION The average particle size of tungsten powders is widely measured using Fisher’s Sub-Sieve-Sizer (hereinafter referred to as the F-SSS) method. ASTM and Fisher’s specifications, which dictate their use, state that the porosity versus particle size plot is plotted on the abscissa and the particle size on a horizontal or porosity scale is Fisher’s