Thermally induced phase transformations of Al93Fe4Nb3 and Al90Fe7Nb3 quenched alloys

Abstract

Al–based rapidly quenched alloys of composition Al _90 Fe _7 Nb _3 and Al _93 Fe _4 Nb _3 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 Al _6 Fe metastable phase. At higher than 709.6 K annealing temperatures the structural transformations of this phase into mix of stable Al _13 Fe _4 compound and aluminium were observed and at 893 K these transformations were completed.

Keywords

• Al-based alloys
• quenching
• crystallization