Structure of liquid Al–Mn–Cr alloys in equilibrium with the μAl4(MnyCr1−y) approximant phase

The structure of liquid Al88.5(MnxCr1−x)11.5 alloys (0≤x≤1) in equilibrium with the hexagonal μAl4(MnyCr1−y) approximant phase (0≤y≤1) was investigated by neutron scattering. The nature of the Mn/Cr substitution in these liquids was assumed to be isomorphic on the basis of preliminary results, showing that a complete Mn/Cr isomorphic substitution does occur in their primary solidified μ-phase. From the analysis of the partial pair distribution functions, as well as from the comparison between experimental and simulated structure factors at large Q values, we found that liquids exhibit a strong local icosahedral order similar to the one observed in Al–Mn and Al–Cr approximant phases, i.e. icosahedral clusters formed by one transition metal surrounded by 12 atoms, mainly Al.