A new icosahedral Al-Fe-Ta alloy prepared by rapid solidification

A new icosahedral phase in the Al-Fe-Ta system has been produced by rapid solidification. The formation of the icosahedral phase is limited in the vicinity of 20%Fe and 10%Ta.The icosahedral phase consists of grains with a size of about 200 nm and each grain includes a highdensity of internal defects showing a contrast of radiating branches. Heating at 10 K/min gives rise to the decomposition of the icosahedral phase into Al₃Fe and Al₃Ta at about900 K. It is thus concluded that the icosahedral phase has considerably higher thermal stabilitythan Al-Mn and Al-Cr binary icosahedral alloys.