Počet záznamů: 1
Structure and phase transformations in gas atomized AlCoCrFeNi high entropy alloy powders
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SYSNO ASEP 0552563 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Structure and phase transformations in gas atomized AlCoCrFeNi high entropy alloy powders Tvůrce(i) Karlsson, D. (SE)
Beran, Přemysl (UJF-V) RID, ORCID, SAI
Riekehr, L. (SE)
Tseng, J. (DE)
Harlin, P. (SE)
Jansson, U. (SE)
Cedervall, J. (SE)Celkový počet autorů 7 Číslo článku 162060 Zdroj.dok. Journal of Alloys and Compounds. - : Elsevier - ISSN 0925-8388
Roč. 893, FEB (2022)Poč.str. 8 s. Forma vydání Tištěná - P Jazyk dok. eng - angličtina Země vyd. CH - Švýcarsko Klíč. slova High-entropy alloy ; HEA ; Diffraction ; X-ray scattering ; Neutron scattering ; Additive manufacturing Obor OECD Materials engineering Výzkumná infrastruktura Reactors LVR-15 and LR-0 II - 90120 - Centrum výzkumu Řež s.r.o.
CANAM II - 90056 - Ústav jaderné fyziky AV ČR, v. v. i.Způsob publikování Open access Institucionální podpora UJF-V - RVO:61389005 UT WOS 000714750200004 EID SCOPUS 85117683263 DOI 10.1016/j.jallcom.2021.162060 Anotace In this study, the crystal structure and phase stability of gas atomized equiatomic AlCoCrFeNi powder was investigated. This alloy is usually described as a high entropy alloy forming a solid solution phase stabilized by a high mixing entropy. However, thermodynamic calculations show that the high entropy phase is stable only at very high temperatures close to the melting point and that a mixture of several phases are the most stable state at lower temperatures. This suggest that kinetic effects may influence the phase composition of atomized powder. The unique features of X-ray diffraction, neutron diffraction as well as transmission electron microscopy were used to study the atomic structure of the atomized powder in detail. The results show that the powder crystallises in an ordered B2 (CsCl-type) structure with a preferred site occupation of Al and Fe on the (1/2 1/2 1/2) position and Co and Ni on the (0 0 0) position. During heat-treatment of the powder, the B2 phase decomposes into fcc and sigma phases and the final phase composition is highly dependent on the heating rate. The effect of heat-treatment on the atomized powder was also investigated and revealed a significant phase transformation with e.g. the formation of sigma phase preferably at the surface of the powder particles. The phase content was also dependent on the size fraction of the powder particles. Sintering of green bodies made with different heat cycles showed that the phase composition of the starting material had a significant impact on the final phase composition and microstructure of the sintered components. The results illustrate the importance of well-defined powder materials for powder consolidation, especially additive manufacturing (binder jetting) of high entropy alloys. Pracoviště Ústav jaderné fyziky Kontakt Markéta Sommerová, sommerova@ujf.cas.cz, Tel.: 266 173 228 Rok sběru 2023 Elektronická adresa https://doi.org/10.1016/j.jallcom.2021.162060
Počet záznamů: 1