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arXiv · 2610.23286

The effect of oxygen on the surface tension of AlTi metallic alloys

Yuna Kato·Jürgen Brillo·Thomas Voigtmann·Linnea Heitmeier
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Abstract

We perform molecular dynamics (MD) simulations of AlTi metallic alloy melts, with a specific focus on surface properties and the effect of oxygen. The simulations use a machine-learned inter- action potential (MLIP) that has recently been tested through experimental data for the statical and dynamical properties of AlTi melts in the bulk [Kato et al. (2026)]. We find that the surface- tension response to oxygen depends strongly on the AlTi composition. Element-resolved density profiles show that oxygen enrichment near the interface is accompanied by a suppression of the Al surface segregation observed in the oxygen-free liquid. The results are compared to experimental values obtained using levitation techniques in microgravity.

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Yuna Kato, Jürgen Brillo, Thomas Voigtmann, Linnea Heitmeier. 2026-10-16. The effect of oxygen on the surface tension of AlTi metallic alloys. https://arxiv.org/abs/2610.23286

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