Formation of Icosahedral Al-Mn and Al-Ru by Solid-State Processes

摘要

We have used ion beam mixing and solid-state interdiffusion of interdigitated Al/Mn or Al/Ru layers to form icosahedral surface alloys in the solid state. Higher temperatures are required to form the icosahedral phase in Al-Ru than in Al-Mn, both with mixing (300 deg C versus 150 deg C) and by interdiffusion (400 deg C versus 300 deg C). Annealing to higher temperatures produces a transformation to more stable crystalline phases. Formation by these techniques indicated that these icosahedral phases nucleate and grow in the solid state in preference to crystalline phases of lower free energy. (ERA citation 11:047951)