Thermally induced phase transformations of Al93Fe4Nb3 and Al90Fe7Nb3 quenched alloys

Al-based rapidly quenched alloys of composition Al90Fe7Nb3 and Al93Fe4Nb3 were studied by Mӧssbauer spectroscopy, X-ray powder diffraction and differential scanning calorimetry methods. The occurrence of thermally induced phase transformations has been established. It is shown that both ribbons reveal the structure in which Fe-atoms have an aluminum ones neighbors both in amorphous and annealed up to 653 K that corresponds to the atomic arrangement in Al6Fe metastable phase. At higher than 709.6 K annealing temperatures the structural transformations of this phase into mix of stable Al13Fe4 compound and aluminium were observed and at 893 K these transformations were completed.