A new Measurement of Thermal Conductivity of Iron at high pressures and temperatures

Pinku Saha; Goutam Dev Mukherjee

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arXiv · 1609.05088

A new Measurement of Thermal Conductivity of Iron at high pressures and temperatures

Pinku Saha·Goutam Dev Mukherjee

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Abstract

Thermal conductivity of the most abundant element in the planetary core, Iron (Fe) is measured up to Earth's outer core pressure $\sim 120$ GPa. The measurements are carried out using the laser heated diamond anvil cell facility, where the absorbed power by Fe metal foil is calculated using thermodynamical equation. The thermal conductivity of $\gamma-Fe$ linearly increases up to a maximum experimental pressure 40 GPa. Thermal conductivity of $\epsilon-Fe$ measured by us shows a saturated value $\sim$ 52 ($\pm$ 5) $Wm^{-1}K^{-1}$ in the pressure range 77 - 120 GPa. At different pressures temperature dependence of thermal conductivity show a sharp drop during melting, which indicates the formation of liquid layer resulting in a thermal buffer to the heat conduction.

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Pinku Saha, Goutam Dev Mukherjee. 2016-09-16. A new Measurement of Thermal Conductivity of Iron at high pressures and temperatures. https://arxiv.org/abs/1609.05088

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