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A small sealed Ta crucible for thermal analysis of volatile metallic samples

Y. Janssen·M. Angst·K. W. Dennis·P. C. Canfield·R. W. McCallum
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Abstract

Differential thermal analysis on metallic alloys containing volatile elements can be highly problematic. Here we show how measurements can be performed in commercial, small-sample, equipment without modification. This is achieved by using a sealed Ta crucible, easily fabricated from Ta tubing and sealed in a standard arc furnace. The crucible performance is demonstrated by measurements on a mixture of Mg and MgB$_2$, after heating up to 1470$^{\circ}{\rm C}$. We also show data, measured on an alloy with composition Gd$_{40}$Mg$_{60}$, that clearly shows both the liquidus and a peritectic, and is consistent with published phase diagram data.

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Y. Janssen, M. Angst, K. W. Dennis, P. C. Canfield, R. W. McCallum. 2005-11-03. A small sealed Ta crucible for thermal analysis of volatile metallic samples. https://doi.org/10.1063/1.2202923

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