During our experiments, we conducted multiple rotary degassing treatments with Ar and N2 purging gases on a 356 alloy with 200 ppm Sr. We found that the fading process of the added modifier is accelerated when nitrogen was used (The Sr concentration decreased and the thermal analysis results showed lower eutectic undercooling). Is it possible that nitrogen forms a compound with the strontium present in the melt? We found no thermodynamic data available for strontium nitrides with various stochiometry, so we could not calculate Gibbs energy of formation values at different temperatures.

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