Quasicrystalline Phase Formation of the Al67Cu26Fe15 Alloy

Abstract

The present work aimed to characterize the microstructure of the icosahedral phase (quasicrystalline phase-f)of the system with stoichiometric composition of the quasicrystal Al67Cu26Fe15. The ternary alloy with nominal composition of Al67Cu26Fe15 was processed by High Power Mechanical Milling as a viable solid state processing method for producing various metastable and stable quasicrystalline phases. The structural characterization of the obtained samples was performed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), while the elemental composition was determined by dispersive energy spectroscopy (DES). On the surface of the quasicrystalline alloy, we can observe in the SEM the presence of -Al2O3 alumina, which contributes to the textural properties of the catalytic support, revealing its catalytic activity,aiming at a higher performance in methanol oxidation reactions. The diffraction patterns of Al67Cu26Fe15 showed the presence of w-Al7Cu2Fe, b-Al(Fe;Cu) and l-Al13Fe4 phases that coexist with the thermodynamic quasicrystalline phase-?. Finally, elemental analysis indicates that during alloy synthesis there is little variation of the ideal composition. The results indicate that alloys with high percentage of icosahedral phase can be obtained by casting in the air.

Keywords

• high power mechanical milling
• quasicrystal al67cu26fe15