Mechanical alloying as a solid state route for fabrication of Al-Cu-M(=Fe, Cr) quasicrystalline phases

Almost single phase quasicrystalline powders consisting of icosahedral Al65Cu23Fe12 and decagonal Al73Cu11Cr16 phases were produced by mechanical alloying (MA) and subsequent heat-treatment. Microstructure, particle size distribution, chemical and phase composition of crystalline powder precursors forming under MA from elemental powders of Al, Cu, Fe and Cr were investigated. Phase transformations leading to formation of quasicrystals during heating of precursors were determined by differential thermal analysis and X-ray diffraction. The growth of quasicrystalline grains studied by SEM is discussed.