Mg gas infiltration for the fabrication of MgB2 pellets using nanosized and microsized B powders

MgB2 superconductor pellets were synthesized through Mg gas infiltration method using nanosized-and microsized B powders. There was a marked difference in the superconducting properties of the two samples, particularly in the pinning force and dominant pinning mechanism. The microstructures of the samples were observed using HR-TEM and STEM-HAADF, and the results showed that the primary reason for the difference in the superconducting properties is the distribution of the nanosized second-phase particle MgO. Additionally, a feasible reaction model for the Mg gas infiltration method was established. Compared to the Mg liquid infil-tration method, the gas infiltration showed better penetrability ability with a small amount of residual Mg. This study presents a novel synthesis process to fabricate an MgB2 pellet with superior density and superconducting properties. This method can be used in multiple applications such as superconducting bearings, compact su-perconductor magnets, and magnetic shielding.

Automated summary

This study synthesized MgB2 superconductor pellets with superior properties using the Mg gas infiltration method, and identified the primary reason for the difference in superconducting properties by observing the microstructure. This method has various potential applications.