High-angle annular dark-field (HAADF) images of a melt-quenched A170Ni15Fe15 decagonal quasicrystal have been taken using a scanning transmission electron microscope for the first time. We have found that the alloy is composed of 2-nm-diameter atom clusters with fivefold symmetry. We have also observed an inversion domain structure. A structural model has been constructed on the basis of the HAADF images and the fivefold cluster of the monoclinic τ2-Al13Co4 approximant model. Antiphase shifts at domain boundaries have been observed directly for the first time. The present observation has verified the results of high-resolution electron microscopy (HREM) and the dark-field imaging technique obtained by Tsuda et al.
|Journal||Japanese Journal of Applied Physics, Part 2: Letters|
|Issue number||6 A/B|
|Publication status||Published - 1999 Jun 15|
ASJC Scopus subject areas
- Physics and Astronomy(all)