凝固冷却速率影响下Al-Pd-Co复杂合金相的形成及分布特征  

Effect of cooling rate on the formation and distribution of Al-Pd-Co complex alloy

作　　者：刘镇洋[1] 孙威[1] 

机构地区：[1]北京工业大学固体微结构与性能研究所,北京100024

出　　处：《电子显微学报》2010年第4期311-316,共6页Journal of Chinese Electron Microscopy Society

基　　金：国家自然科学基金资助项目(No.10774010)

摘　　要：复杂合金相具有不同于传统金属的结构特征。为了搞清凝固冷却条件对铸态Al-Pd-Co复杂合金相存在状态的影响,本文应用TEM、SEM、HREM、EDS等多种电子显微学手段,分析了不同凝固冷却速率下Al70Pd10Co20三元合金中复杂合金相形成和分布特征。通过比较不同凝固冷却速率下凝固组织的形貌和成份的变化,推断出Al70Pd10Co20合金凝固过程中,M-Al13Co4和O-Al13Co4型复杂合金相的高温形成具有宽化的成分区间。随着凝固冷却速率的提高可导致另一具有复杂结构的W相的形成并与M-Al13 Co4和O-Al13 Co4型相共生,其结构包含与Al-Pd-Co十面体准晶同类的十面体原子团结构单元。Complex metallic alloy phases（CMAPs） are a kind of phases whose structural characteristics are significantly different from those of traditional metals.In order to clarify the existing state of as-cast Al-Pd-Co CMAPs affected by cooling rate during the solidification,a combination of multiple electron microscopy techniques including TEM,SEM,HREM and EDX have been applied to investigate the formation and distribution characteristics of CMAPs in the Al70 Pd10 Co20 alloy solidified with different cooling rates.Insights from comparing structural,morphological and compositional variations of solidification structures formed with different cooling rate during the solidification suggest that CMAPs of M-Al13Co4 and O-Al13Co4 types can be formed in a broad compositional range at high temperature.Increasing the cooling rate during the solidification can result in formation of another CMAP W-phase,whose structure is constructed with atom clusters of the same type as those in the Al-Pd-Co decagonal quasicrystal.The W-phase can coexist with intergrowing M-Al13Co4 and O-Al13Co4type CMAPs to form a mixed structure.

关 键 词：复杂合金相 电子显微技术 Al-Pd-Co 凝固冷却速率 结构分析 

分 类 号：TG111.4[金属学及工艺—物理冶金]