Formation of a quasicrystalline phase in mechanically alloyed Al65Cu25Fe15

An elemental powder mixture with a nominal composition of Al65Cu20Fe15 was mechanically milled for times of up to 8 h. Subsequent annealing of as-milled powders was performed at different temperatures between 600 and 800 deg. C for 4 h. A combination of X-ray diffractrometry, differential scanning calorimetry and transmission and scanning electron microscopy has been used to characterise the microstructure of as-milled powders before and after annealing. The icosahedral quasicrystalline (QC)-phase did not form directly after milling. QC-phase was obtained from the un-milled powder by annealing above 700 deg. C for 4 h. However, a combination of milling and subsequent annealing could enhance the formation of QC at temperatures above 600 deg. C