Short-range order in undercooled and stable melts forming quasicrystals and approximants and its influence on nucleation
نویسندگان
چکیده
An icosahedral short-range order has been predicted to prevail in undercooled metallic melts. For melts of pure metals this hypothesis was recently experimentally confirmed by diffraction experiments. This work presents results of neutron scattering experiments on the short-range order of stable and undercooled liquids of alloys forming quasicrystals and polytetrahedral crystals. The studies indicate that an icosahedral topological short-range order prevails in all of the investigated melts. The influence of this icosahedral short-range order on the nucleation behaviour of solid phases from the undercooled liquid is discussed.
منابع مشابه
Short-range Order in Undercooled Melts and Its Impact on the Solidification Behaviour
As suggested by Frank [1] an icosahedral short-range order should be energetically favoured in undercooled metallic melts. Such a short-range order is predicted to influence the energy of the interface between the liquid and a solid nucleus, depending on the structure of the solid phase [2]. This in turn decisively impacts the nucleation behaviour of solid phases from the undercooled melt, and ...
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