Abstract

The Fe 1.1 Se 0.5 Te 0.5 polycrystalline superconductors were prepared by a high-energy ball-milling (HEBM) technique. Ball-milling times of 0, 2, 4, 6, and 8 h were adopted to optimize this technique. The influences of ball-milling time on the phase distributions of milled powders and sintered bulks, the morphology of ball-milled powders, and superconducting properties of final sintered bulks were systematically studied. It was found that with increasing ball-milling time, the ball-milled powders changed from a crystal to a noncrystalline and then to an alloy. At the same time, the main phases in ball-milled powders changed from original mixed powders of Fe, Se, and Te to (Se, Te) solid solution, and then to the two phases of β-Fe(Se, Te) and δ -Fe(Se, Te), accordingly. Due to the reduction in diffusion length, it was more likely for HEBM powders to form FeSeTe ternary alloys. Thus, the obtained Fe(Se, Te) bulk with HEBM time of 4 h exhibited the highest T c of 14.3 K and the largest content of superconducting phase. However, in the samples achieved by longer HEBM time, phase segregation and oxidation were observed. Therefore, the HEBM time of 4 h is the most suitable for the fabrication of high-quality precursor powders according to these experiments.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.