Metastable phase boundaries of quasicrystalline phases

Abstract

The melting curve T₀ of the metastable icosahedral phase and the liquidus of the decagonal phase of AlMn have been obtained for 14–22 at.% Mn. Icosahedral AlMn has a congruent melting point of 910±20°C at 20 at.% Mn and melts about 30°C lower than crystalline compounds with the same composition. Icosahedral Al₈₂Ru₁₈ was determined to melt at 1260±30°C. These results were obtained by forming single-phase icosahedral alloys with ion beam mixing and then rapidly heating to accurately known temperatures with electron beams.