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arXiv · 2309.01062

Validation of the Wiedemann-Franz Law in solid and molten tungsten above 2000 K through thermal conductivity measurements via steady state temperature differential radiometry

Milena Milich·Hunter B. Schonfeld·Konstantinos Boboridis·Davide Robba·Luka Vlahovic·Rudy Konings·Jeffrey L. Braun·John T. Gaskins·Niraj Bhatt·Ashutosh Giri·Patrick E. Hopkins
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Abstract

We measure the thermal conductivity of solid and molten tungsten using Steady State Temperature Differential Radiometry. We demonstrate that the thermal conductivity can be well described by application of Wiedemann-Franz Law to electrical resistivity data, thus suggesting the validity of Wiedemann-Franz Law to capture the electronic thermal conductivity of metals in their molten phase. We further support this conclusion using ab initio molecular dynamics simulations with a machine-learned potential. Our results show that at these high temperatures, the vibrational contribution to thermal conductivity is negligible compared to the electronic component.

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Milena Milich, Hunter B. Schonfeld, Konstantinos Boboridis, Davide Robba, Luka Vlahovic, Rudy Konings, Jeffrey L. Braun, John T. Gaskins, Niraj Bhatt, Ashutosh Giri, Patrick E. Hopkins. 2023-09-03. Validation of the Wiedemann-Franz Law in solid and molten tungsten above 2000 K through thermal conductivity measurements via steady state temperature differential radiometry. https://arxiv.org/abs/2309.01062

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