Chen, S.K. and Xu, X and Kim, J.H. and Dou, S.X. and MacManus-Driscoll, J.L. (2010) The effects of C substitution and disorder on the field dependent critical current density in MgB2 with nano-SiC additions. PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS , 470 (20). ISSN 0921-4534
Full text is not hosted in this archive but may be available via the Official URL, or by requesting a copy from the corresponding author.
In this work, nano sized SiC powders were mixed with Mg and B and reacted by either a one-step in situ 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 H-irr and H-c2 at 20 K in comparison to samples with mainly unreacted SiC (hence lower C substitution). More importantly, their J(c)'s are more insensitive to high magnetic field (>4 T) at 6 K. However, at 20 K the effect of C content on J(c)(H) is less pronounced. Finally, the order of magnitude of J(c)(H) at both 6 K and 20 K is rather dominated by pinning. (C) 2010 Elsevier B.V.
|Subjects:||Material Science > Nanostructured materials|
|Deposited On:||28 Oct 2010 10:14|
|Last Modified:||28 Oct 2010 10:14|
Repository Staff Only: item control page