Electron Diffraction and Microscopy Techniques for Studying Grain‐Boundary Structure

Abstract

Electron microscopy and diffraction techniques for studying grain‐boundary structure are reviewed. The experimental conditions for applying strong‐beam, weak‐beam, and lattice imaging and electron diffraction are described and examples from recent studies in ceramics, semiconductors, and metals are used to illustrate the information that these techniques provide. It is demonstrated that electron diffraction can be used to study both the periodic nature of the boundary layer and its thickness. A particularly valuable feature of weak‐beam imaging is that it can provide information on the details of the dislocation structure of the boundary, whereas strong‐beam imaging can be used to determine the rigid‐body translation between neighboring grains across special boundaries; these translations can be significantly smaller than the resolution of the microscope. Finally, lattice imaging can provide information on the location of dislocations and steps in the boundary.