An electron microscopic study was made of defects in plastically deformed single crystals of the intermetallic ξ′-phase. Pure edge dislocations, with 2 different Burgers vector directions and 4 different Burgers vector magnitudes, were found. All of the observed Burgers vector magnitudes could be described in terms of irrational fractions of the unit-cell parameters. Burgers vector directions were observed that could be indexed by using irrational indices. The observed stacking faults had displacement vectors whose magnitudes and directions were incompatible with the unit cell of the ξ′ phase. A comparison of the Burgers vectors observed here, with those reported for the corresponding icosahedral quasicrystal, showed that they were equivalent with respect to their directions and lengths. It was concluded that local order, rather than long-range periodic or quasi-periodic order, governed the structures of defects in these materials.

Structure of Dislocations and Stacking Faults in the Complex Intermetallic ξ′-(Al-Pd-Mn) Phase. H.Klein, M.Feuerbacher: Philosophical Magazine, 2003, 83[36], 4103-22