New developments of computer-aided crystallographic analysis in transmission electron microscopy

A new computer program for on-line crystallographic analysis in transmission electron microscopy (TEM) is presented. The program is based on the fast online determination of single-crystal orientations from Kikuchi and spot patterns. Spot patterns, which are particularly useful in the case of highly deformed metals, are analyzed by a new digital image processing procedure. This procedure improves the precision and ease of the orientation measurement. The program permits the on-line measurement of glide systems characterized by the Burgers vector and the crystallographic line direction of dislocations and their glide planes. The determination of twin systems, based on the misorientation calculation for any crystal structure, is included as well. The possibility of determining the foil thickness permits the complete crystallographic characterization of interfaces. Finally the program facilitates the discrimination of phases and includes the fit of the lattice parameters a, b and c from diffraction patterns. The new procedures are described in detail. Application examples are given for all functions.