Structure and properties of "pseudo NiTi" and "pseudo NiAl" multi-component high entropy shape memory intermetallicsThursday (17.05.2018) 11:35 - 12:00 Part of:
High temperature shape memory alloys (HTSMA), most of which are intermetallic compounds, have been considered as perspective functional materials. Yet, their application is hindered due to diffusion and plastic deformation processes that intensify at the high service temperatures . On the other hand, once the race for HTSMA kept going for almost 2 decades, practically at the same time, Yeh and co-authors produced an impressive breakthrough in structural materials’ design by proposing entirely new concept of high-entropy alloys (HEA) . Recently, following the HEA concept, the novel class of functional materials - high entropy shape memory alloys has been identified [3,4]. These advanced functional materials are, in fact, intermetallic multi-component prototypes of NiTi that belong to (TiZrHf)50(CoNiCu)50 family and possess a peculiar distorted structure . The present report intends to show that high entropy approach allowed to generate an extra multi-component prototypes of NiAl intermetallic compound. It will be shown though their comparison how the peculiarities of the crystal and electronic structure of (TiZrHf)50(CoNiCu)50 and (CoNiCu)50(AlGaIn)50 high entropy intermetallic compounds result in the advanced properties of these promising high temperature shape memory alloys.
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 B.S. Murty, Jien-Wei Yeh, S. Ranganathan, High Entropy Alloys, Elsevier Science & Technology Butterworth-Heinemann Ltd, Oxford (2014).
 G.S. Firstov, T.A. Kosorukova, Yu.N. Koval, V.V. Odnosum, Materials Today: Proceedings, 2S (2015), S499-S504.
 G.S. Firstov, T.A. Kosorukova, Yu.N. Koval, P. A. Verhovlyuk, Shape memory and Superelasticity, 1 (2015), 400-407.
 G. Firstov, A. Timoshevskii, T. Kosorukova, Yu. Koval, Yu. Matviychuk, P.Verhovlyuk, MATEC Web of Conferences, 33 (2015), 06006.
Keywords: crystal and electronic structure, martensitic transformation, elevated temperatures, high entropy shape memory alloys