To understand the formation of the Bergman cluster in the F-type icosahedral quasicrystal, crystallographic relations between the quasicrystal and the intermetallic-compound H and Zn23Y6 phases in the Zn-Mg-Y alloy system were investigated mainly by transmission electron microscopy. It was found that, although sample rotations of about 1° were required to obtain simple crystallographic relations, the orientation relationship was established among the cubic-Fm3m Zn23Y6 structure, the hexagonal-P63/mmc H structure, and the F-type icosahedral quasicrystal (IQ); that is, c // the fivefold axis in the IQ // N(21 10)H, and c // the twofold axis in the IQ // N(0553)H, where N(hkml)H means the normal direction of the (hkml)H plane in the H structure. The correspondences between atomic positions in the Bergman cluster and in the Zn23Y6 structure and between those in the cluster and in the H structure were investigated on the basis of the established relationship. As a result, an assembly of six short-penetrated-decagonal columns was identified as an appropriate nucleus in the formation of the Bergman cluster from these two structures.
|Publication status||Published - 2017 Oct 9|
- Bergman cluster
- Icosahedral quasicrystal
- Transmission electron microscopy
- Zn-Mg-Y alloy system
ASJC Scopus subject areas