Structural features, stacking faults, and grain boundaries in MgB2 superconducting materials

TL;DR

This study investigates the structural features, stacking faults, and grain boundaries in MgB2 superconductors using advanced microscopy and simulations, revealing how synthesis conditions influence microstructure and superconducting performance.

Contribution

It provides detailed analysis of MgB2 microstructure and its relation to synthesis pressure and superconducting properties, combining experimental and theoretical approaches.

Findings

MgB2 has a hexagonal P6/mmm structure.

Microstructure varies with synthesis pressure.

Stacking faults and grain boundaries are linked to high critical current density.

Abstract

The structural properties of MgB2 superconductors have been analyzed by means of convergent-beam electron diffraction, high-resolution transmission-electron microscopy, and theoretical simulations. The MgB2 crystal has been identified to have a hexagonal structure with the space group of P6/mmm. Microstructural features of MgB6 materials depend evidently upon the synthesis pressures. Stacking faults and grain boundaries in a sample with the critical current density greater than 105A/cm2 have been extensively investigated.