Improved Superconducting Properties in Bulk MgB2 Prepared by High Energy Milling of Mg and B Powder

TL;DR

This study demonstrates that high energy milling of Mg and B powders significantly improves the microstructure and superconducting properties of MgB2 bulk materials, achieving high critical current densities at low temperatures.

Contribution

The paper introduces high energy milling as an effective method to produce fine crystalline MgB2 with enhanced superconducting performance.

Findings

Critical current density of 2.0×10^6 A/cm^2 at 15K and 0.59T

Microstructure with grain size 40-100 nm

Improved grain connectivity and superconducting properties

Abstract

The MgB2 bulks were prepared by high energy milling of Mg and B powder. The correlations among milling times, microstructure and superconducting properties were investigated in MgB2 bulks. Samples were characterized by x-ray diffraction (XRD), energy dispersive spectrometry (EDX) and scanning electron microscope (SEM), and the magnetization properties were examined by a Superconducting quantum interfere device (SQUID) magnetometer. It showed that the high energy milling is an effective approach to get fine crystalline (40-100nm) bulk MgB2 with good grain connectivity and high Jc performance. The critical current density reaches to 2.0X10E6A/cm2 at 15K and 0.59T, 5.7X10E5A/cm2 at 2T and 3.0X10E4A/cm2 at 5T.