Preparation method of nano composite ytrium barium copper oxide superconducting bulks

Abstract

The invention discloses a preparation method of nano composite ytrium barium copper oxide superconducting bulks, which comprises the steps of preparing solid phase powder, preparing liquid phase source powder, pressing precursor bulks, assembling the precursor bulks, carrying out infiltrated growth on nano composite ytrium barium copper oxide single-domain bulks, and carrying out oxygen permeation treatment. By taking a mixture of Y2O3 nano powder, BaCuO2 precursor powder and CeO2 initial powder as solid phase powder, after high-temperature infiltration and slowly-cooled growth are performed, nanoscale Y2BaCuO5 particles are successfully introduced into ytrium barium copper oxide superconducting bulks, so that higher superconducing properties are obtained. By taking a mixture of Yb2O3, and BaO, CuO initial powder as liquid phase source powder, the whole infiltrated growth process is implemented by only using BaCuO2 precursor powder, so that the method is simple in process and high in efficiency. The invention also can be used for preparing nano composite superconducting materials of Nd, Sm and Gd series and the like.

Description

technical field [0001] The invention belongs to the technical field of high-temperature copper oxide superconducting materials, and in particular relates to a method for preparing a nanocomposite yttrium-barium-copper-oxygen superconducting bulk material. Background technique [0002] The single-domain RE-Ba-Cu-O (REBCO, RE=Y, Gd, Sm, Nd, etc.) high-temperature superconducting bulk material guided by top-seed technology effectively solves the problem of grain boundaries in polycrystalline samples and multi-domain samples The "weak connection" phenomenon that exists at the place can carry a higher body critical current, showing higher magnetic flux capture and magnetic levitation performance. It has broad application prospects. [0003] By doping RE 2 BaCuO 5 Precursor powder in REBa 2 Cu 3 o 7?δ Introducing Diffusely Distributed Tiny REs into a Superconducting Matrix 2 BaCuO 5 Particles can significantly improve the flux pinning ability of REBCO superconducting bulk ...

AI Technical Summary

Problems solved by technology

For this reason, people have tried to convert the nanoscale RE 2 BaCuO 5 The precursor powder is doped into the REBCO superconducting bulk material, however, due to the REBa 2 Cu 3 o 7?δ The crystal growth and solidification process is very slow, RE 2 BaCuO 5 Particles enriched in RE 3+ The Ba-Cu-O liquid phase will undergo a serious Ostwald coarsening and growth process, and the RE captured in the final sample 2 BaCuO 5 The average particle size of the particles is still increased to between submicron and 1 micron, which cannot play the most effective role of magnetic flux pinning

If there is no strong enough magnetic flux pinning center in the superconductor, its unimpeded current-carrying capacity will be limited, resulting in low capture magnetic flux and magnetic levitation performance of the sample, which cannot meet the technical indicators required for practical applications.

Moreover, the low magnetic flux pinning force cannot prevent the flux creep caused by thermal activation of the high-temperature superconductor when it works in the liquid nitrogen temperature region (77K), so there is a serious problem of capturing magnetic flux and magnetic levitation force decaying over time.

The existence of these problems has seriously affected the practical value and practical application process of this kind of material.

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