A classification of symmetrical grain boundaries

Abstract

A classification of all symmetrical grain boundaries and their tilt rotation axes based on a geometrical construction expressing the relationship between the interplanar spacing and the orientation of the normal to the boundary plane is introduced for the f.c.c. and b.c.c. lattices. It is shown that the favoured grain boundaries found by computer simulations for different models of interatomic forces are in agreement with the boundaries which belong to low levels of the classification schemes. It is anticipated that this classification, which is different from the classification based on the planar density of atomic sites, is a useful guide-line on the search for symmetrical boundaries that possess special properties.