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Information × Registration Number 0222U003441, 0117U002134 , R & D reports Title Structure and properties of disordered materials based on aluminum and magnesium synthesized under conditions of high impact popup.stage_title Head Rud Oleksandr D., Доктор фізико-математичних наук Registration Date 23-03-2022 Organization Institute of Metal Physics. G.V. Kurdyumov of the National Academy of Sciences of Ukraine popup.description2  The processes of phase formation that take place in the conditions of high-energy processing of the initial elementary powders of aluminum and magnesium in the presence of sparingly soluble components have been comprehensively studied. For the first time the metastable Al3Mg β″-phase of L12 structural type was prepared by mechanical alloying in the planetary mill under the argon gas atmosphere. The effect of graphite and scandium on the formation of the metastable intermetallic Al3Mg phase was studied. It was found that the graphite suppresses the powder agglomeration. The additional alloying by scandium accelerates the process of Al3Mg phase formation. Bulk composite materials based on the Al3Mg phase are fabricated using a spark plasma sintering technique. The Vickers hardness values for SPS sintered pellets are more than twice as high as that of duralumin. The structure of the liquid Al87Mg13 alloy has been investigated by high-temperature X-ray diffraction, reverse Monte Carlo simulations, and the Voronoi diagram method. Quantitative characteristics of the short-range order (the number of the nearest neighboring atoms, the radius of the first coordination sphere, the distribution of valence angles), which determine the topology of the atomic configurations of the melt, have been analyzed. It was found that on the distributions of valence bond angles for the generated models of configurations of Al-Al-Al atoms there are positions typical for icosahedral structures. Statistical analysis of Voronoi polyhedra showed they are characterized by a wide distribution in the number of faces, among which pentagonal ones predominate, and topological indices what is inherent to disordered structures. The arrangement of coordination polyhedra with shapes close to distorted icosahedra, which were built around the Al atoms with topological characteristics, has been revealed. Product Description popup.authors Velichko Lubov A. Dzyublenko Mykola I. Kirian Inna M. Kucherenko Kira A. Lepeeva Julia V. Lakhnik Andrii M. Marunyak Oleksandr V. popup.nrat_date 2022-03-23 Close