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http://dx.doi.org/10.9714/psac.2018.20.3.011

Effects of surface-treated boron powder using chemical solvents on MgB2 bulk superconductors  

Lim, J.Y. (Department of Materials Engineering, Andong National University)
Ahn, J.H. (Department of Materials Engineering, Andong National University)
Ranot, M. (Korea Institute of Materials Science)
Oh, Y.S. (Korea Institute of Materials Science)
Kang, S.H. (Korea Institute of Materials Science)
Jang, S.H. (Kiswire Advanced Technology Ltd)
Hwang, D.Y. (Kiswire Advanced Technology Ltd)
Chung, K.C. (Korea Institute of Materials Science)
Publication Information
Progress in Superconductivity and Cryogenics / v.20, no.3, 2018 , pp. 11-14 More about this Journal
Abstract
$MgB_2$ superconducting properties have been investigated with the surface-treated boron powders using the chemical solvents. Various solvents were used such as acetone, ethanol, methanol, and water to possibly modify the surface condition of raw boron powders as received. This treatment was done at an argon gas environment inside the glove box to reduce the further contamination during and after chemical treatments. It was found that $T_c$ values were increased to 37.58-37.73 K from the pure sample of 37.50 K when they were treated in inert environment. High- fields $J_c$ at both 5 & 20 K was all increased regardless of any kinds of chemical treatments mentioned above. It is also noted that the $J_c$ at low-fields were increased in the order of solvents: ethanol > acetone > pure $MgB_2$ = methanol > water.
Keywords
$MgB_2$; superconductor; chemical treatment; surface reaction;
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