摘要
采用等温差示扫描量热分析(DSC)和透射电镜(TEM)观察相结合的方法,研究了Zr65Cu12.5Ni10Al7.5Ag5非晶合金玻璃转变和晶化过程。利用DSC对合金晶化过程实时监控,在加热到不同温度随炉冷却退火后对样品进行TEM分析,观察其不同阶段的微观结构变化,揭示其晶化特征。结果发现:Zr65Cu12.5Ni10Al7.5Ag5急冷合金晶化过程分为3段。初期晶化相为二十面体准晶I相,在I相与非晶基体之间没有明显的成分差异,准晶相相比于非晶基底略富Zr贫Cu;初期二十面体准晶相形核密度高生长迅速,通过消耗非晶相紧密堆积生长;晶化第1阶段结束后仍有残余非晶相存在。
Microstructure evolvement during crystallization process for the melt-spun Zr65Cu12.5Ni10Al7.5Ag5 amorphous alloy has been studied by DSC analysis and TEM. We monitor the crystallization process by DSC, and stop at given temperatures, following by cooling down from these temperatures in the DSC furnace to examine the corresponding microstructure evolvement by TEM. The results show that the crystallization of Zr65Cu12.5Ni10Al7.5Ag5 alloy can be divided into three stages. At the initial stage, an icosahedral quasi-crystal （I-phase） is formed as primary phase from the amorphous matrix without apparent compositional variation. In comparison with the amorphous matrix, the I-phase is Zr-rich and Cu-poor slightly with high nucleation and growth rates by consuming the amorphous matrix, leading to a microstructure with closed packed grains at the first stage of crystallization. However, the residual amorphous phase still exists at this stage.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2008年第5期823-826,共4页
Rare Metal Materials and Engineering
基金
国家自然科学基金(50571002)
北京市教委人才强教基金资助
关键词
Zr基玻璃合金
晶化
热分析
电子显微结构
Zr-based glassy alloy
quasi-crystallization
thermal analysis
electron microscopy structure
