International Conference on the Structure and Properties of Internal Interfaces
J. Phys. Colloques 46 (1985) C4-231-C4-236
DOI: 10.1051/jphyscol:1985425
COINCIDENCE ORIENTATIONS OF GRAINS IN HEXAGONAL MATERIALS
H. Grimmer1 et D.H. Warrington21 Swiss Federal Institute for Reactor Research, CH-5303 Würenlingen, Switzerland
2 Department of Metallurgy, Sheffield University, U.K.
Abstract
For arbitrary rotations expressed in hexagonal coordinates, the connection between an axis-angle quadruple and the rotation matrix is given. The relation between hexagonally equivalent quadruples is stated and a unique reduced quadruple is defined. Rotations generating coincidence site lattices (CSLs) correspond to quadruples of coprime integers if a2/c2 is rational. The multiplicity Σ of the CSL is not always equal to the least common denominator of the elements in the rotation matrix. The case a = c is considered in detail.