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

• Main Authors: Mohd Hapipi, Nurhidayah, Chen, Soo Kien, Shaari, Abdul Halim, Awang Kechik, Mohd Mustafa, Lim, Kean Pah, Tan, Kar Ban, Lee, Oon Jew, Arvapalli, Sai Srikanth, Miryala, Muralidhar
• Format: Article
• Published: Springer 2022
• Online Access: http://psasir.upm.edu.my/id/eprint/101260/; https://link.springer.com/article/10.1007/s10854-022-08101-3#:~:text=In%20this%20work%2C%20ex%20situ,the%20decomposition%20of%20MgB2.

In this work, ex situ MgB2 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 MgB2. Onset of critical temperature, Tc, was retained at ∼ 38 K even after the addition of Mg. By increasing the sintering temperature, magnetic critical current density, Jc at self-field, and 20 K of the ex situ samples increased consistently. With the addition of Mg for 1 h sintering, self-field Jc (20 K) was enhanced more than 20 times to 104 A cm−2 as the sintering temperature was increased. Such significant enhancement in the Jc is mainly due to the improved grain coupling aided by Mg during the short sintering.