Electron tomography: An imaging method for materials deformation dynamics

• Published in: Current opinion in solid state & materials science Vol. 24; no. 4; p. 100850
• Main Authors: Hata, S., Honda, T., Saito, H., Mitsuhara, M., Petersen, T.C., Murayama, M.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2020
• Subjects: Diffraction contrast; Dislocation dynamics; Electron tomography (ET); In-situ observation; Plastic deformation; Three-dimensional (3D); Transmission electron microscopy (TEM); Three-dimensional (3D); Electron tomography (ET); Plastic deformation; In-situ observation; Transmission electron microscopy (TEM); Dislocation dynamics; Diffraction contrast
• ISSN: 1359-0286
• DOI: 10.1016/j.cossms.2020.100850

•The current achievement of three-dimensional (3D) material deformation imaging in transmission electron microscopy (TEM) is reviewed.•Morphological changes in a deformable specimen and dislocation movements in a crystalline specimen have been visualized in three dimensions at a time resolution of several minutes using TEM.•Technical issues on developing 3D imaging methods of dislocation dynamics in TEM will be discussed from various aspects. The combination of in-situ and three-dimensional (3D) in transmission electron microscopy (TEM) is one of the emerging topics of recent advanced electron microscopy research. However, to date, there have been only handful examples of in-situ 3D TEM for material deformation dynamics. In this article, firstly, the authors briefly review technical developments in fast tilt-series dataset acquisition, which is a crucial technique for in-situ electron tomography (ET). Secondly, the authors showcase a recent successful example of in-situ specimen-straining and ET system development and its applications to the deformation dynamics of crystalline materials. The system is designed and developed to explore, in real-time and at sub-microscopic levels, the internal behavior of polycrystalline materials subjected to external stresses, and not specifically targeted for atomic resolution (although it may be possible). Technical challenges toward the in-situ ET observation of 3D dislocation dynamics are discussed for commercial structural crystalline materials, including some of the early studies on in-situ ET imaging and 3D modeling of dislocation dynamics. A short summary of standing technical issues and a proposed guideline for further development in the 3D imaging method for dislocation dynamics are then discussed.