Fabrication of nano-crystalline W-Ni-Fe pre-alloyed powders by mechanical alloying technique
来源期刊:中国有色金属学报(英文版)2009年增刊第3期
论文作者:晏建武 刘莹 彭阿芳 卢全国
文章页码:711 - 717
Key words:tungsten based high-density alloy; mechanical alloying; high energy ball milling; nano-crystalline; low temperature sintering
Abstract: Nano-crystalline pre-alloyed powders of W-Ni-Fe were fabricated by high energy ball milling mechanical alloying (MA) technique. The change of appearances and the crystallite sizes of powders before and after high energy ball milling were investigated by XRD, TOPAS P software, SEM and EDS. The results show that the nano-crystalline pre-alloyed powders can be fabricated by 5 h high energy ball milling. During the MA process, the diffusion of W, Ni and Fe happens in the process of repeated welding and fracturing. As a result, nano-crystalline supersaturated solid solutions are formed. The crystallite sizes won’t be refined after 10 h ball milling. The crystallite sizes of different compositions are almost the same under the same MA condition. Due to the toughening mechanism of rare earth element, the powders of 90W-4Ni-2Fe-3.8Mo-0.2RE alloy are seriously agglomerated after ball milling compared with the other alloys. It can be concluded that the optimal sintering temperature of 90W-4Ni-2Fe-3.8Mo-0.2RE pre-alloyed powders after 15 h mechanical alloying is 1 300-1 350 ℃.
基金信息:the Education Science Foundation of Jiangxi Provincial Education Department
the Natural Science Foundation of Jiangxi Province, China