Abstract
A great number of the actual applications of the superconductivity uses metallic superconductors capable
to transport high current densities. The optimization of the flux pinning in these conductors is extremely
important to increase the critical density current. The design of the microstructure projected to serve as
pinning centers has been presented as one highly promising technique for the optimization of the
transport properties of these materials [1]. However, due to the nanometric dimensions of these artificial
pinning centers, the profiles of heat treatment used for the reaction and formation of the superconducting
phase must be analyzed carefully, considering the distinct distributions and compositions of the
composites (pinning centers + superconducting phase), in comparison with the conventional materials
[2]. In the present work, the objective is to get a methodology for optimization of the heat treatments
profile of diffusion, reaction and formation of the superconducting phases in materials with pinning
centers in nanometric scale. The distribution and the composition of the pinning centers inside of the
superconducting phase were determined by MEV-FEG and MEV+EDS, respectively. The results of
pinning force Fp, and the maximum critical current density that the superconductor can support were
measured under the influence of an applied magnetic field.
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