Liquid aluminum containing the important alloying element magnesium in varying concentrations was analyzed using in-situ laser-induced breakdown spectroscopy (LIBS). Magnesium emission shows an exponential dependence on melt temperature that correlates well with the expected partial pressure of magnesium above the aluminum melt. Furthermore, comparison with LIBS measurements on corresponding solid samples supports the conclusion that a significant part of Mg emission from liquid metal samples originates from the vapor phase above the metal surface. Simultaneously, curves of growth measured over four orders of magnitude in Mg concentration reveal a level of self-absorption for liquid aluminum samples that is stronger than for solid aluminum samples having a corresponding Mg concentration, and beyond what is expected from conventional plasma models. The implications for measurements of volatile species in liquid metals in general are discussed.

中文翻译：

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液态铝中镁激光诱导等离子体发射的气相贡献。

使用原位激光诱导击穿光谱（LIBS）对含有不同浓度的重要合金元素镁的液态铝进行了分析。镁的排放量显示出对熔体温度的指数依赖性，这与铝熔体上方的镁的预期分压密切相关。此外，与相应固体样品的 LIBS 测量结果进行比较，得出这样的结论：液态金属样品中 Mg 排放的很大一部分源自金属表面上方的气相。同时，测量的 Mg 浓度超过四个数量级的生长曲线表明，液态铝样品的自吸收水平强于具有相应 Mg 浓度的固态铝样品，并且超出了传统等离子体模型的预期。讨论了一般液态金属中挥发性物质测量的含义。