Defocus convergent beam electron diffraction analysis of dislocations in mullite.

Burgers vectors of matrix dislocations in mullite have been determined by the defocus large-angle convergent beam electron diffraction technique. Vectors of the types [100], [010], [110] and [112] were identified. These Burgers vectors are discussed in relation to the open channels and the oxygen vacancy distribution in the mullite structure. It is suggested that a short-range ordering of oxygen vacancies may account for a Burgers vector of the type [112]. [ABSTRACT FROM AUTHOR]