Coherent scattering domain measurements in Al-Cu-Fe alloys during<i>in situ</i>heating
Abstract
Al-Cu-Fe quasicrystalline alloys were recently developed as bulk amorphous advanced materials with high potential for applications like high-temperature thermal barriers, lowfriction and wear-resistant coatings [1-4], composite biomaterials [5] or catalysts [6]. The crystallization of asprepared alloys plays a crucial role in the technological application of these new materials. The nucleation and growth of nanoscale phases in these alloys during constant rate heating was investigated using high-resolution hightemperature powder X-ray diffraction. A series of nanocrystalline Al-based alloys were synthesized by mechanical alloying. The temperature stability of the Al-Cu-Fe alloy was investigated by in-situ angular-dispersive Xray diffraction at the B2 high-resolution diffractometer at HASYLAB. Constant heating rate annealing experiments were performed in inert gas atmosphere in order to analyse the evolution of phase constituents. The X-ray diffraction (XRD) patterns ( = 0.65125 ) were collected in transmission mode during heating up to 800C. The formation of the single icosahedral quasicrystalline -phase is the main crystallization event. The temperature dependence of the average coherent scattering domains was obtained using the Scherrer equation. Further analysis of the diffraction pattern are in progress, with the aim to resolve the temperature evolution of strain during constant rate heating and the crystallization kinetics.