High-field thermal transport properties of REBCO coated conductors

TL;DR

This study investigates the longitudinal thermal conductivity of REBCO coated conductors under high magnetic fields up to 19 T, providing essential data for thermal stability analysis of superconducting devices.

Contribution

First comprehensive measurement of REBCO coated conductors' thermal conductivity in high magnetic fields, validating estimation methods based on electrical properties.

Findings

Zero-field thermal conductivity can be predicted within 15% accuracy.

High-field measurements support the use of Wiedemann-Franz law for in-field conductivity estimation.

Data aids in thermal stability analysis of high-temperature superconductor magnets.

Abstract

The use of REBCO coated conductors is envisaged for many applications, extending from power cables to high-field magnets. Whatever the case, thermal properties of REBCO tapes play a key role for the stability of superconducting devices. In this work, we present the first study on the longitudinal thermal conductivity ($\kappa$) of REBCO coated conductors in magnetic fields up to 19 T applied both parallelly and perpendicularly to the thermal-current direction. Copper-stabilized tapes from six industrial manufacturers have been investigated. We show that zero-field $\kappa$ of coated conductors can be calculated with an accuracy of $\pm 15%$ from the residual resistivity ratio of the stabilizer and the Cu/non-Cu ratio. Measurements performed at high fields have allowed us to evaluate the consistency of the procedures generally used for estimating in-field $\kappa$ in the framework of the Wiedemann-Franz law from an electrical characterization of the materials. In-field data are intended to provide primary ingredients for the thermal stability analysis of high-temperature superconductor-based magnets.