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Synthesis of Mg(B$_{1-x}$C$_x$)$_2$ Powders

R. H. T. Wilke·S. L. Bud'ko·P. C. Canfield·D. K. Finnemore·S. T. Hannahs
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Abstract

We have synthesized bulk Mg(B$_{1-x}$C$_x$)$_2$ from a mixture of elemental Mg, B, and the binary compound B$_4$C. Carbon incorporation was dramatically improved by a two step reaction process at an elevated temperature of 1200 $^o$C. This reaction process results in a solubility limit near x$\sim$0.07. We found that impurities in the starting B cause an additive suppression of T$_c$. We combine these data with T$_c$ and H$_{c2}$(T=0) data from CVD wires as well as plasma spray synthesized powders and present a unifying H$_{c2}$ and T$_c$ versus x plot.

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R. H. T. Wilke, S. L. Bud'ko, P. C. Canfield, D. K. Finnemore, S. T. Hannahs. 2005-07-06. Synthesis of Mg(B$_{1-x}$C$_x$)$_2$ Powders. https://doi.org/10.1016/j.physc.2005.08.007

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