The effects of C substitution and disorder on the field dependent critical current density in MgB2 with nano-SiC additions
RIS ID
33919
Abstract
In this work, nano sized SiC powders were mixed with Mg and B and reacted by either a one-step insitu or two-step method resulted in different level of C substitution. X-ray diffraction shows the presence of Mg2Si signifying that the reaction between SiC and Mg occurred leading to the release of C in samples reacted in one-step method. Moreover, the much reduced value of a-axis indicates C substitution took place. Resistivity measurements showed higher intragrain scattering owing to a higher density of defects and/or impurities. These samples also show higher Hirr and Hc2 at 20 K in comparison to samples with mainly unreacted SiC (hence lower C substitution). More importantly, their Jc’s are more insensitive to high magnetic field (>4 T) at 6 K. However, at 20 K the effect of C content on Jc(H) is less pronounced. Finally, the order of magnitude of Jc(H) at both 6 K and 20 K is rather dominated by pinning.
Grant Number
ARC/DP0770205
Publication Details
Chen, S. K., Xu, X., Kim, J., Dou, S. Xue. & MacManus-Driscoll, J. (2010). The effects of C substitution and disorder on the field dependent critical current density in MgB2 with nano-SiC additions. In Proceedings of the 22nd International Symposium on Superconductivity (ISS 2009), 2-4 Nov, 2009, Tsukuba, Japan. Physica C: Superconductivity and its Applications, 470 (20), 1211-1215.