Spatial variation of superconducting properties of Gd123 bulk superconductors with magnetic particles addition

摘要

Magnetic flux trapping and the homogeneity of the flux pinning are essential problems in the practical application of high-temperature superconductors. We have conducted study on the role of addition of soft magnetic Fe-B alloy particles contribute to the enhancement of the critical current density (J_c) under wide-range of magnetic field. Magnetic flux trapping was enhanced in Gd123 bulk superconductor with suitable amount of magnetic particles addition. In addition, it can be effective as pinning center enhance the J_c of the bulk in both the a-b growth sector and the c-growth sector under magnetic field. However, the T_c of the Gd123 bulk was decreased obviously by addition of magnetic particles. The study on the spatial variation of superconducting properties indicates that the performance of the upper part of the bulk is better than the bottom. By comparing the superconducting properties of the Gd123 bulk with magnetic particles addition and without magnetic particles addition, we concluded that there is a trace of the formation of homogeneous pinning properties in the magnetic particles addition Gd123 bulk.