A transmission electron microscopy study of tweed-like structures in Al₆₂Cu_17.5Co_17.5Si₃ decagonal quasicrystals

Abstract

A tweed-like structure with striated contrast has been observed in an Al₆₂Cu_17.5Co_17.5Si₃ decagonal quasicrystal, for the first time, by using conventional electron diffraction contrast imaging and high-resolution electron microscopy images. The contrast of these striations, as observed under two-beam conditions, is different from that resulting from dislocations, stacking faults and small-angle grain boundaries in quasicrystals, and it can be interpreted as being due to quasilattice distortions introduced by the lattice misfit between the decagonal quasicrystal matrix and the local ordering.