The quasicrystalline phase formation in Al-Cu-Cr alloys produced by mechanical alloying

Research highlights: → Formation of decagonal quasicrystalline phase in Al-Cu-Cr alloys. → Obtained decagonal phase belongs to D3 family of decagonal quasicrystals. → Decagonal phase has 1.26 nm periodicity along 10-fold axis. → Alloys were produced by combination of mechanical alloying and subsequent annealing. → Phase composition of as-milled powders depending on annealing temperature. - Abstract: Almost single-phase decagonal quasicrystal with periodicity of 1.26 nm along 10-fold axis was produced in Al69Cu21Cr10 and Al72.5Cu16.5Cr11 alloys using combination of mechanical alloying (MA) and subsequent annealing. Phase transformations of as-milled powders depending on annealing temperature in the range of 200-800 deg. C are examined. Since the transformations can be explained based on kinetic and thermodynamic reasons it seems that applied technique (short preliminary MA followed by the annealing) permits to produce the equilibrium phases rather than metastable ones.