Determination of the Burgers Vector of a Boundary Dislocation by Weak-Beam High Voltage Electron Microscopy

Burgers vector of an isolated boundary dislocation is determined rigorously from weak-beam micrographs with diffracting vectors common to the adjoining crystals by equating three sets of equations, g_i (x,y,z) b (x,y,z)=n_i (i=1,2,3). The common diffraction plane is rather limited in number but weak-beam micrographs with sufficient number of extinction contours were obtained for principal diffractions up to 311 in a thin and smoothly polished specimen foil under a high voltage electron microscope. The technique is useful in determining the Burgers vector of imperfect boundary dislocations such as a facet dislocation.