FIB加工、扫描及透射电子显微镜相结合的复杂合金相层状组织表征

Lamellar microstructure in the complex alloy phases by focused ion beam processing, scanning and transmission electron microscopy

扫描电子显微镜(SEM)与聚焦离子束(FIB)可集成为双束系统,实现微区形貌观察与样品加工一体化,同时也可实现截面薄样品的定位提取。利用该技术并结合透射电镜(TEM)技术研究了Al-Pd-Fe复杂合金系铸态组织中层片结构的构成与分布特征。结果表明,铸态Al_(75)Pd_(15)Fe_(10)合金中的层片组织由M-Al_(13)Fe_4相与准晶相构成。通过对比发现,相同层片组织在背散射电子像与透射电镜观察下呈现出明显不同的分布特征。结合扫描与透射电子显微学成像原理,阐明了SEM和TEM两种表征方式产生不同结果的原因,指出了通过SEM,FIB以及TEM相结合对表征微细多相混合组织真实三维空间分布特征的必要性和有效性。

Scanning electron microscopy(SEM)and focused ion beam(FIB)can be incorporated into a dual beam system which allows microscopic observation,in-situ processing and thin cross-section sample extraction to be realizable.By means of a combination of this system with transmission electron microscopy(TEM),the constitution and distribution for the lamellar structure formed in the as-cast Al 75 Pd 15 Fe 10 alloy have been investigated.The results show that the lamellar structure consists of M-Al 13 Fe 4 and quasicrystal phases.It is found that the distribution feature for the lamellar structure revealed by transmission electron microscopy and that by the backscattered electron imaging are obviously different.The reason for this has been clarified based on their distinctive imaging principles,through which one can realize that a combination of SEM,FIB and TEM is necessary and effective in order to characterize the real three-dimensional distribution features for fine mixtures of multiple-phases.