Transport and magnetic Jc of MgB2 strands and small helical coils

TL;DR

This study investigates the critical current densities of MgB2 strands with SiC additions and heat treatments, revealing improvements in high-field transport Jc at low temperatures and insensitivity to heat treatment variations.

Contribution

It provides new insights into how SiC additions and heat treatment parameters affect MgB2 strands and coils' superconducting performance.

Findings

SiC improves high-field Jc at 4.2 K

Transport Jc is insensitive to heat treatment variations

No significant improvement at 1 T across temperatures

Abstract

The critical current densities of MgB2 monofilamentary strands with and without SiC additions were measured at 4.2 K. Additionally, magnetic Jc at B = 1 T was measured from 4.2 K to 40 K. Various heat treatment times and temperatures were investigated for both short samples and small helical coils. SiC additions were seen to improve high field transport Jc at 4.2 K, but improvements were not evident at 1 T at any temperature. Transport results were relatively insensitive to heat treatment times and temperatures for both short samples and coils in the 700C to 900C range.