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Enhancement of the critical current density and flux pinning of MgB2 superconductor by nanoparticle SiC doping

S. X. Dou·S. Soltanian·J. Horvat·X. L. Wang·P. Munroe·S. H. Zhou·M. Ionescu·H. K. Liu·M. Tomsic
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Abstract

Doping of MgB2 by nano-SiC and its potential for improvement of flux pinning was studied for MgB2-x(SiC)x/2 with x = 0, 0.2 and 0.3 and a 10wt% nano-SiC doped MgB2 samples. Co-substitution of B by Si and C counterbalanced the effects of single-element doping, decreasing Tc by only 1.5K, introducing pinning centres effective at high fields and temperatures and enhancing Jc and Hirr significantly. Compared to the non-doped sample, Jc for the 10wt% doped sample increased by a factor of 32 at 5K and 8T, 42 at 20K and 5T, and 14 at 30K and 2T. At 20K, which is considered to be a benchmark operating temperature for MgB2, the best Jc for the doped sample was 2.4x10^5A/cm2 at 2T, which is comparable to Jc of the best Ag/Bi-2223 tapes. At 20K and 4T, Jc was 36,000A/cm2, which was twice as high as for the best MgB2 thin films and an order of magnitude higher than for the best Fe/MgB2 tapes. Because of such high performance, it is anticipated that the future MgB2 conductors will be made using the formula of MgBxSiyCz instead of the pure MgB2.

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S. X. Dou, S. Soltanian, J. Horvat, X. L. Wang, P. Munroe, S. H. Zhou, M. Ionescu, H. K. Liu, M. Tomsic. 2002-07-09. Enhancement of the critical current density and flux pinning of MgB2 superconductor by nanoparticle SiC doping. https://doi.org/10.1063/1.1517398

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