The characterization of periodic dislocation arrays from the fine structure of electron diffraction patterns

Abstract

SUMMARYThe accuracy of the technique of using the fine‐structure observed in electron diffraction patterns to determine the periodicity and characteristic direction associated with a periodic strain field is assessed. This is done by applying the technique to dislocation multipoles which have a strain field with only a single periodic component and which can be well characterized by other means. It is shown that, for such a single‐component strain field, precision measurement of the diffraction patterns combined with numerical analysis of the data allows the determination of the direction and spacing characterizing the strain field with an accuracy of about 0.25° to 1.0° in direction (depending upon periodicity) and ± 2% in spacing. This is better than can usually be achieved from measurements of corresponding features in the electron micrographs.