REBCO delamination by transverse electromagnetic stress due to screening current in magnetic field

TL;DR

This paper investigates how transverse electromagnetic stress from screening currents in high magnetic fields causes delamination in REBCO coated conductors, which is critical for their use in ultra-high field magnets.

Contribution

It introduces a method to characterize delamination strength of REBCO tapes under electromagnetic stress induced by screening currents in high magnetic fields.

Findings

Screening currents induce electromagnetic stress leading to delamination.

Experimental results demonstrate the stress behavior up to 35 T.

Potential application for quality assurance in magnet manufacturing.

Abstract

REBCO coated conductor has great potential to be used in ultra-high field magnets. Commercial REBCO tapes are strong in the longitudinal direction but prone to delamination by tensile stress in the thickness direction. For high field magnet applications, it is crucial to characterize delamination strength of REBCO conductor and better manage the transverse electromagnetic stress. In this work, the electromagnetic stress in high magnetic fields by screen current is used to study the delamination behavior of commercial REBCO tapes. Screening currents are induced in REBCO by either ramping field or rotating sample in magnetic fields up to 35 T. The experimental results are presented. The prospect of using this method for quality assurance in large magnet projects is discussed.