摘要
本文利用球差校正透射电子显微镜对钯基金属玻璃薄膜的剪切带微观结构进行了研究。在低角环形暗场像中观察到,剪切带中存在纳米晶,但纳米晶没有造成剪切带宽度发生变化和分剪切带的出现,这表明纳米晶可能是剪切带形成之后所产生的。此外,本文进一步对基体和剪切带的环形暗场像强度和径向分布函数进行了分析发现,与基体相比,剪切带中原子分布更加无序和松散,同时原子键长变大,这些表明剪切带中发生了大范围的原子重排,导致自由体积含量增加和原子密度降低。本文研究结果为进一步理解金属玻璃薄膜的形变机制和精确调控其力学性能提供了指导。
In this paper,the microstructure of shear bands of Pd⁃based metallic glass thin films was investigated by a spherical aberration⁃corrected transmission electron microscopy.It can be observed in the low⁃angle annular dark field images that nanocrystals existed in shear bands,but the nanocrystals did not cause the change of the width of shear bands and the appearance of new shear bands.These indicate that the nanocrystals may be formed after the formation of shear bands.In addition,we further analyzed the intensity of annular dark field image and radial distribution function of the matrix and the shear bands.Compared with the matrix,the distribution of atoms in shear bands is more disordered and looser,meanwhile the atomic bond lengths become lager,which indicates that the atomic rearrangement in wide range occurs in shear bands,causing the increase in the free volume content and the decrease in the atomic density.These result provide guidance for further understanding the deformation mechanism of metallic glass thin films and the method of precisely controlling their mechanical properties.
作者
姜红玉
温玉仁
刘明
张庆华
谷林
JIANG Hong-yu;WEN Yu-ren;LIU Ming;ZHANG Qing-hua;GU Lin(Institute of Physics,Chinese Academy of Sciences,Beijing 100190;Material Science and Engineering School,University of Science and Technology Beijing,Beijing 100083;QianXuesen Laboratory of Space Technology,China Academy of Space Technology,Beijing 100094)
出处
《电子显微学报》
CAS
CSCD
北大核心
2022年第4期387-392,共6页
Journal of Chinese Electron Microscopy Society
关键词
金属玻璃薄膜
剪切带
原子结构
透射电子显微镜
metallic glass thin films
shear bands
atomic structure
transmission electron microscopy