Abstract
Bulk discs (20 mm diameter and 4.3 mm thickness) of MgB2 added with Ge2C6H10O7 were obtained by Spark Plasma Sintering. Six samples with composition MgB2(Ge2C6H10O7)0.0014 and one undoped sample were fabricated under similar conditions and were magnetically characterized in order to determine the scattering of properties and reproducibility. The main source of the scattering of the properties is the decomposition of the additive due to elimination of the organic part in gas form, which occurs stepwise with intensive vacuum drops at around ~ 560 and ~ 740 °C. A third drop, which is sometimes not well resolved being part of the second peak at 740 °C, occurs at ~ 820 °C. The critical temperature at the midpoint of the transition, Tc, shows only a relatively small variation between 37.4 and 38 K, and the irreversibility field at a low temperature of 5 K takes values between 8 and 10 T. The pinning force and pinning force related parameters do not correlate with the carbon substituting for boron in MgB2 and suggest a synergetic influence of the microstructural details and carbon. Overall, despite the superconducting properties scattering, the samples are of high quality. Stacked into a column of six samples, they can trap at the center and on the surface of the column a magnetic field of 6.78 and 5.19 T at 12 K, 5.20 and 3.98 T at 20 K and 2.39, and 1.96 T at 30 K. These promising values, combined with facile fabrication of the samples with relatively high quality and reproducibility, show the feasibility of their use in building complex and large compound arrangements for bulk magnets and other applications.
Highlights
Bulk discs (20 mm diameter and 4.3 mm thickness) of MgB2 added with Ge2C6H10O7 were obtained by Spark Plasma Sintering
The addressed aspects are among the key priorities of the research in the applied superconductivity community and through the study proposed in this work, we provide several arguments in favor of small bulks and for their use in compound magnets and other applications
Small spark plasma sintered discs of M gB2 added with G e2C6H10O7 were obtained for fixed spark plasma sintering (SPS) processing conditions and raw materials
Summary
Bulk discs (20 mm diameter and 4.3 mm thickness) of MgB2 added with Ge2C6H10O7 were obtained by Spark Plasma Sintering. Stacked into a column of six samples, they can trap at the center and on the surface of the column a magnetic field of 6.78 and 5.19 T at 12 K, 5.20 and 3.98 T at 20 K and 2.39, and 1.96 T at 30 K These promising values, combined with facile fabrication of the samples with relatively high quality and reproducibility, show the feasibility of their use in building complex and large compound arrangements for bulk magnets and other applications. In our work we fabricated by ex situ spark plasma sintering (SPS) high density MgB2 bulks, pristine and with different additives[25]. The fabrication of M gB2 bulks has some general drawbacks:
Sign-in/Register to view highlights & summary 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 callDisclaimer: 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.
