摘要
用真空吹铸法制备了直径为2mm的Mg65Cu25Y10-xTbx(x=0,2,4,6,8,10)块体非晶合金棒,采用X射线衍射分析(XRD)、差热分析(DTA)分别对非晶合金的结构和形成能力进行了研究。结果表明:Mg65Cu25Y10-xTbx合金均能形成非晶合金;随着合金元素Tb含量的增加其玻璃形成能力逐渐增强,当x=8时,合金的玻璃形成能力最强,随后当x=10时,有所下降。通过对Mg65Cu25Y10-xTbx合金系的电负性差与原子尺寸参数的计算,合理地解释了产生这一现象的原因可能是由于Mg65Cu25Y10-xTbx合金的电负性差的变化所引起的;当x=6,8时,合金的玻璃形成能力较强,DTA图显示其成分可能属于共晶点成分,同时通过计算得出此两种非晶合金的λ值与由原子团族模型推导出的λ=0.18相差较大。
The bulk Mg65Cu25Y10-xTbx （x=0, 2, 4, 6, 8, 10） amorphous alloy rods of 2 mm in diameter were prepared by a copper mold casting method. The structure and glass forming ability of the alloys were analyzed by X-ray diffraction （XRD） and differential thermal analysis （DTA）, respectively. It is shown that all of the Mg65Cu25Y10-xThx （x=0, 2, 4, 6, 8, 1 0） alloys can be prepared into bulk amorphous alloys, the glass forming ability of the alloys becomes stronger with the increment of Th content. It is the strongest when x=8 then drops at x= 1 0, which can be explained reasonably by calculating the electro-negativity difference △x and the atomic size parameter for the alloys. The single smooth melting peak in the DTA pattern indicates that the alloys with a stronger glass forming ability may be eutectic composition when x=6 and 8. The atomic structure parameter λ of the two amorphous alloys is far from 0.18, which is deduced from the atom cluster model.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2006年第7期1154-1157,共4页
Rare Metal Materials and Engineering
基金
甘肃省自然科学基金(ZS032-B25-018)
关键词
镁基非晶合金
电负性差
玻璃形成能力
热稳定性
共晶点成分
magnesium based amorphous alloy
electro-negativity difference
glass-forming ability
thermal stability
eutectic composition
