High energy ball milling of a Al65Cu20Fe15 quasicrystalline alloy

The phase transformations of the quasicrystals and related crystalline phases present in an Al65Cu20Fe15 alloy were studied by high energy ball milling. The milling was carried out in an attritor mill at speeds of 200 and 400 rpm for 5, 10, 20 and 40 h with a ball to charge ratio of 20:1, using hexane as a process control agent. As-cast and milled samples were annealed at 500 °C for 7 days. All of the specimens were characterized by optical, scanning, X-ray diffraction and differential thermal analysis. The sample compositions were determined by energy dispersive X-ray analysis and electron spectroscopy for chemical analysis. The results of the present investigation are discussed in light of the current understanding of the phase stability in complex systems.