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DOE OSTI · 1644081

Thermal interfaces in dynamic compression experiments

Hartsfield, T. M.·La Lone, B. M.·Stevens, G. D.·Veeser, L. R.·Dolan, D. H.
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Abstract

Temperature is a difficult thermodynamic variable to measure in dynamic compression experiments. Optical pyrometry is a general-purpose technique for measuring temperature from a radiant surface, but that surface is often the interface between distinct materials with temperatures that vary spatially along the loading direction. This leads to a fundamental problem: how does the measured interface temperature relate to this temperature profile along the compression axis? Numerical analysis of loading history and thermal diffusion at these interfaces shows that seemingly subtle changes in experiment geometry can lead to very different temperature profiles. We compare these results to laboratory temperature measurements of shock-compressed tin.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSHistory and philosophy of scienceMaterials propertiesPhysical quantitiesShock compressionShock testingShock wavesSound source perceptionState functionsTemperature metrologyThermal diffusionpyrometry, thermal diffusion, shock temperatures, hugoniot state temperatures, direct impact, thermal interfaces

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Hartsfield, T. M., La Lone, B. M., Stevens, G. D., Veeser, L. R., Dolan, D. H.. 2020-07-07. Thermal interfaces in dynamic compression experiments. https://doi.org/10.1063/5.0012524

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