Pinning behavior in bulk MgB.sub.2./sub. prepared using boron powder refined via high-energy ultra-sonication

0545185 - FZÚ 2022 RIV US eng J - Článek v odborném periodiku
Arvapalli, S.S. - Miryala, M. - Jirsa, Miloš - Sakai, N. - Murakami, M.
Pinning behavior in bulk MgB₂ prepared using boron powder refined via high-energy ultra-sonication.
Journal of Superconductivity and Novel Magnetism. Roč. 34, č. 5 (2021), s. 1297-1301. ISSN 1557-1939. E-ISSN 1557-1947
Grant ostatní: AV ČR(CZ) StrategieAV21/3
Program: StrategieAV
Institucionální podpora: RVO:68378271
Klíčová slova: flux pinning * bulk MgB₂ * boron refinement * ultrasonication
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 1.675, rok: 2021
Způsob publikování: Open access

We successfully refined a cheap commercial boron powder by means of high-energy ultra-sonication and utilized it in synthesis of bulk MgB2. Rietveld phase analysis of X-ray diffraction pattern revealed completely formed MgB2 with a low amount of MgO. MgB2 bulk prepared of boron ultra-sonicated in ethanol for 15 min showed self-field Jc of around 300 kA/cm2 at 20 K without any compromise in Tc (~39 K). Pinning analysis based on Dew-Hughes expression showed major pinning contribution from grain-boundary pinning (~95.5%), along with a slight contribution from point pinning (4.5%). The microstructure study detected a system of large MgB2 grains (hundreds nm large) and 10–20 nm sized particles, possibly Mg-B-O, formed at MgB2 grain boundaries.
Trvalý link: http://hdl.handle.net/11104/0321944