# Thermodynamic framework for assessing dissolutive wetting behaviors in metallic systems

## TL;DR

This study introduces a thermodynamic framework to explain how liquid metal spreads on solid metals, which can improve industrial processes like welding and coating.

## Contribution

A new thermodynamic framework is established to assess dissolutive wetting behaviors in metallic systems.

## Key findings

- Three distinct wetting behaviors were identified in nine metallic systems.
- Two key thermodynamic parameters, CL and CR, control solid solution formation and dissolutive wetting.
- DFT calculations reveal atomistic mechanisms influencing solid solution formation.

## Abstract

Despite its significance in practical applications, until today dissolutive wetting in metallic systems remains poorly understood due to the intricate liquid/solid interactions. In this study, we investigate nine metallic systems encompassing a vast range of thermodynamic behaviors. Our findings reveal three distinct wetting behaviors and identify two key thermodynamic parameters that control solid solution formation and then dissolutive wetting behaviors, namely the solubility of the substrate element in the liquid (\documentclass[12pt]{minimal}
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\begin{document}$${C}_{L}$$\end{document}CL) and the solidification composition range (\documentclass[12pt]{minimal}
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\begin{document}$${C}_{R}$$\end{document}CR). We observe a slow spreading due to the step flow mechanism in systems with a relatively low \documentclass[12pt]{minimal}
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\begin{document}$${C}_{L}$$\end{document}CL and narrow \documentclass[12pt]{minimal}
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\begin{document}$${C}_{R}$$\end{document}CR. For systems with high \documentclass[12pt]{minimal}
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\begin{document}$${C}_{L}$$\end{document}CL, the spreading begins relatively fast and transitions to the step flow mechanism when \documentclass[12pt]{minimal}
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\begin{document}$${C}_{L}$$\end{document}CL is reached. Systems with a large \documentclass[12pt]{minimal}
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\begin{document}$${C}_{R}$$\end{document}CR, conversely, exhibit consistently fast spreading. Density functional theory (DFT) calculations provide deeper insights into the underlying atomistic mechanisms affecting the solid solution formation. Our results offer inspiration for optimizing high-temperature processing techniques, such as welding, coating and high temperature infiltrating.

This study establishes a new thermodynamic framework that explains how solid metal dissolution controls liquid metal spreading, advancing understanding in high-temperature wetting field and improving industrial processes such as welding and coating.