Enhanced critical current density of ex situ MgB2 via control of Mg assisted sintering

• Published in: Journal of materials science. Materials in electronics 2022-05, Vol.33 (14), p.11257-11268
• Main Authors: Hapipi, Nurhidayah Mohd, Chen, Soo Kien, Shaari, Abdul Halim, Kechik, Mohd Mustafa Awang, Lim, Kean Pah, Tan, Kar Ban, Lee, Oon Jew, Arvapalli, Sai Srikanth, Miryala, Muralidhar
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Critical current density; Critical temperature; Magnesium compounds; Materials Science; Optical and Electronic Materials; Partial pressure; Sintering
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-022-08101-3

In this work, ex situ MgB 2  was mixed with 0.5 mol of Mg and sintered. The sintering conditions were varied over a temperature range of 600–1000 °C for 1, 3, and 7 h, respectively. The addition of Mg during the sintering increased the partial pressure of Mg and thus suppressed the decomposition of MgB 2 . Onset of critical temperature,  T c,  was retained at ∼ 38 K even after the addition of Mg. By increasing the sintering temperature, magnetic critical current density,  J c  at self-field, and 20 K of the ex situ samples increased consistently. With the addition of Mg for 1 h sintering, self-field  J c  (20 K) was enhanced more than 20 times to 10 4  A cm −2  as the sintering temperature was increased. Such significant enhancement in the  J c  is mainly due to the improved grain coupling aided by Mg during the short sintering.