Formation of Quasicrystalline Aluminium-Vanadium and Aluminium-Chromium Fine Particles by Gas-Evaporation Technique

Abstract

Fine particles in icosahedral phase have been prepared by the gasevaporation method, and studied by electron microscopy. The particles are spherical ranging from 20 to 300 nm in diameter and show a characteristic contrast with an irregular striation. Edge lengths of the fundamental hexahedron in the Penrose tiling are 0.474±0.002 nm in the Al–V system and 0.473 ± 0.003 nm in the Al–Cr system. Though most of the quasicrystalline particles are in a single phase, composite particles of the icosahedral phase and the crystalline phase(β–Al6V) are also observed in the Al–V system. From the orientation relationship between the two phases, atomic sites of vanadium in the icosahedral phase are discussed.