The effect of scandium on the structure, microstructure and superconductivity of equimolar Sc-Hf-Nb-Ta-Ti-Zr refractory high-entropy alloys

Krnel, Mitja (avtor), Jelen, Andreja (avtor), Vrtnik, Stanislav (avtor), Luzar, Jože (avtor), Gačnik, Darja (avtor), Koželj, Primož (avtor), Wencka, Magdalena (avtor), Meden, Anton (avtor), Hu, Qiang (avtor), Guo, Sheng (avtor), Dolinšek, Janez (avtor)

In this study, we investigate the scandium-containing Sc-Hf-Nb-Ta-Ti-Zr system of refractory high-entropy alloys (HEAs). Using the arc-melting method, we synthesized nine equimolar alloys (five 4-, three 5- and one 6-component), with all of them containing Sc. The alloys were characterized by XRD, electron microscopy and EDS, while superconductivity was investigated via electrical resistivity, specific heat and the Meissner effect. The results were compared to the parent Hf-Nb-Ta-Ti-Zr refractory HEAs, forming a single-phase body-centered cubic (bcc) structure and quite homogeneous microstructure. The addition of Sc produces a two-phase structure in the Sc-Hf-Nb-Ta-Ti-Zr alloys, with one phase being bcc and the other hexagonal close-packed (hcp). The hcp phase absorbs practically all Sc, whereas the Sc-poor bcc phase is identical to the bcc phase in the Hf-Nb-Ta-Ti-Zr parent system. Upon the Sc addition, the microstructure becomes very inhomogeneous. Large bcc dendrites (10–100 µm) are homogeneous in the central parts, but become a fine dispersion of sub-micron precipitates of the bcc and hcp phases close to the edges. The interdendritic regions are also a fine dispersion of the two phases. Superconductivity of the Sc-Hf-Nb-Ta-Ti-Zr alloys originates from the bcc phase fraction, which demonstrates identical superconducting parameters as the bcc Hf-Nb-Ta-Ti-Zr parent alloys, while the Sc-containing hcp phase fraction is non-superconducting.

• Jezik: Angleški jezik
• Ključne besede: high-entropy alloys, structure and microstructure, superconductivity
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FMF - Fakulteta za matematiko in fiziko ; FKKT - Fakulteta za kemijo in kemijsko tehnologijo
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2022
• Št. strani: 20 str.
• Številčenje: Vol. 15, iss. 3, art. 1122
• PID: 20.500.12556/RUL-136988
• UDK: 53
• ISSN pri članku: 1996-1944
• DOI: 10.3390/ma15031122
• COBISS.SI-ID: 95789315
• Datum objave v RUL: 27.05.2022

Gradivo je del revije

• Naslov: Materials
• Skrajšan naslov: Materials
• Založnik: MDPI
• ISSN: 1996-1944
• COBISS.SI-ID: 33588485

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.
• Začetek licenciranja: 01.02.2022

Projekti

• Financer: ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
• Številka projekta: P1-0125
• Naslov: Magnetna resonanca in dielektrična spektroskopija pametnih novih materialov

• Financer: Drugi - Drug financer ali več financerjev
• Program financ.: National Science Foundation of China
• Številka projekta: 52061016