Crystallographic characterization of planes in the scanning electron microscope

This study documents the theoretical considerations and experimental procedures for determining lattice plane crystallography in the scanning electron microscope (SEM). The input parameters for the procedure include an orientation component obtained by electron backscatter diffraction and a spatial component obtained either by perpendicular sectioning or calibrated, parallel sectioning. It is significant that the indices of grain boundary planes and microcracks can be determined using the rationales described. Hitherto, the grain boundary plane indices or crack surface indices have been reported infrequently because of the technical challenges involved. The crystallographic characterization of boundary planes in the SEM is illustrated with a data set from annealed nickel. Many boundaries were coincidence site lattice Σ = 3 types, and of these, most had rational indices whereas non Σ = 3 boundaries had irrational indices. The distribution of symmetric and asymmetric boundary types was consistent on the basis of relative energies.