Amorphization and crystallization of Al-Fe alloys by mechanical alloying

The chemical interaction between Al and Fe caused by mechanical alloying of Al-14.3 at.%, Fe and Al-22.8 at.% Fe mixtures has been studied as a function of the mechanical energy dose. The sequence of the structural transformation and the behaviour of mechanically alloyed alloys during the heating has been determined. The investigation methods were X-ray diffractometry, Mossbauer spectroscopy and differential scanning calorimetry. It was found that Al-22.8 at.% Fe and Al-14.3 at.% Fe alloys reached the amorphous state at doses of 130 kJ g(-1) and 340 kJ g(-1) respectively. The increase in the energy dose resulted in the crystallization of amorphous phase and the formation of a quasi-crystalline phase in both alloys. After heating to 1023 K the Al-22.8 at.% Fe quasi-crystalline alloy transformed into a two-phase state and consisted of Al5Fe2 and Al3Fe. A single Al3Fe phase formed after the crystallization of this alloy from the melt.