Transition between periodic and quasiperiodic structures in Al–Ni–Co

Structure of the pseudodecagonal Al–Co–Ni approximant PD4

“…PD4 was obtained from an alloy of nominal composition Al 72.5 Co 18 Ni 9.5 annealed at 900 C for 2150 h [12]. Single crystal X-ray diffraction (XRD) data was collected from a PD4 crystal on an Oxford Xcalibur TM 3 diffractometer with monochromatized Mo Ka radiation.…”

“…The term pseudodecagonal (PD) structure is used for decagonal QC approximants [12]. They are named PD1, PD2 etc.…”

“…They are named PD1, PD2 etc. and exhibit diffraction patterns with almost perfect 10-fold symmetry and quasiperiodic reflection arrangements of the strongest reflections [12][13][14].…”

Twenty years of structure research on quasicrystals. Part I. Pentagonal, octagonal, decagonal and dodecagonal quasicrystals

“…Hiraga, Ohsuna, Nishimura (2001b) studied by HAADF (200 kV) and HRTEM (400 kV) a sample with the same composition Al 71.5 Co 16 Ni 12.5 , which had been longer annealed (900 C, 120 h), however. It resulted to be the orthorhombic PD 3c approximant, Pmn2 1 , a % 52 A, b % 4 A, c % 37 A, (Grushko, Holland-Moritz, Wittmann, 1998), which is related to the type I superstructure. A structure model was presented using the same clusters with pentagonal symmetry that were also found in the superstructure type I.…”

On the evolution of quasicrystalline and crystalline phases in rapidly quenched Al-Co–Cu–Ni alloy

“…Grushko et al [12] have 3 investigated the transition between the periodic and quasi-periodic structures of decagonal Al-Co-Ni alloy of as-cast and annealed condition. The effect of the Si substitution for the conformation of the stability of Al-Cu-Co decagonal phase have been studied [13].…”