Dislocation Cores
- Practical Electron Microscopy and Database -
- An Online Book -

http://www.globalsino.com/EM/  



 
This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.
 

=================================================================================

A dislocation can be observed in TEM because the lattice near the dislocation core is bent elastically. The degree of bending increases when closer to the dislocation core. Dark-field imaging mode, also called weak-beam (WB) technique here, is normally used for dislocation imaging.

Figure 134 shows a STEM Z-contrast image of an 8° [0 0 1] tilt grain boundary in SrTiO3 in the [0 0 1] orientation, indicating two adjacent grains with cubic symmetry and five dislocation cores (dark ovals) at the grain boundary. Figure 134 (b) shows one of the dislocation cores at a higher magnification. The brighter columns surrounding the core represent the Sr columns, while the less bright columns represent the Ti–O columns. Due to the small scattering amplitude of oxygen, the pure O columns are not visible.

Z-contrast image of a 8° [0 0 1] tilt grain boundary in SrTiO3

Figure 134. (a) Z-contrast image of a 8° [0 0 1] tilt grain boundary in SrTiO3, and (b) One of the dislocation cores at a higher magnification. [1]

[1] R.F. Klie, I. Arslan, N.D. Browning, Atomic resolution electron energy-loss spectroscopy, Journal of Electron Spectroscopy and Related Phenomena 143 (2005) 105–115.

 

 

=================================================================================

The book author (Yougui Liao) welcomes your comments, suggestions, and corrections, please click here for submission. If you let book author know once you have cited this book, the brief information of your publication will appear on the “Times Cited” page.