Grain refinement of W-Ni-Fe heavy alloys by tantalum element adding^①

来源期刊：中国有色金属学报(英文版)2004年第2期

论文作者：罗述东 唐新文 易建宏

文章页码：241 - 245

Key words：tungsten heavy alloys; alloying element addition; grain refinement; tantalum

Abstract: 90W-7Ni-3Fe and (90-x)W-xTa-7Ni-3Fe (x=1,3,5,7,10) specimens were attained by liquid phase sintering. A model describing the process of liquid forming and spreading was proposed to point out the differences between alloys doped with tantalum and traditional tungsten heavy alloys. Tantalum priority of entering matrix and a relative high solubility in liquid matrix depress tungsten solubility in liquid matrix, which decreases kinetic rate constantKand conse- quently results in the reduction of W grain size. The grain refinement is influenced by Ta content and becomes more obvious when Ta content is over 5%. The sample with less than 3%Ta has dominant W and matrix phases. While besides W and matrix phases, intermetallic phases emerge in 85W-5Tai-7Ni-3Fe sample. Ta is superfluous and forms a new tantalum phase when more than 7% Ta is added into alloys.