Formation of decagonal and approximant phases in the Al-Ni-Ru system

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

“…Two decagonal phases, one with 4 A and one with 16 A translation period were found in the system Al--Ni--Ru after slow cooling (Sun, Hiraga, 2000a C (Mi, Grushko, Dong, Urban, 2003a, b;Mandal, Hashimoto, Suzuki, Hosono, Kamimura, Edagawa, 2003). The stability range at 1000 C is around Al 73.1 Ni 15.7 Ru 11.2 , at 700 C it is shifted by %1%.…”

“…The quasilattice constant was determined by X-ray powder diffraction to a r ¼ 2.49 A and the periodicity to 16.7 A, respectively (Mandal, Hashimoto, Suzuki, Hosono, Kamimura, Edagawa, 2003). No peak shifts or broadening, indications for linear or random phason strain, respectively, could be observed.…”

The Structure of an Al-Ni-Ru Monoclinic Phase Al<SUB>13</SUB>(Ru,Ni)<SUB>4</SUB>

“…And the important structural information of such interesting crystalline phases in the Al-Ru-Ni system were also discussed by high-resolution electron microscopy. [5][6][7] These crystalline phases are generally referred to as approximants because their local atomic arrangements are similar to those of quasicrystals. In this context, the structural information of an approximant is essential in order to clarify the local structure of the corresponding quasicrystal.…”