Method for 45 degree rare earth barium copper oxygen thin film seed high speed growth superconducting block material

Abstract

The invention relates to a method for promoting the high speed growth of a superconducting bulk material by utilizing a 45-degree rare earth BCO membrane seed crystal. The REBCO membrane with a 45-degree tetrasymmetric structure in plane inner orientation is taken as the seed crystal, and the high temperature superconducting REBCO bulk material is in homoepitaxy growth by a cold seed crystal method. The membrane material has a superheat degree more than 20K on a monocrystalline magnesia substrate, and the unique plane inner orientation can evidently increase the growth speed of the bulk material. The REBCO and an appropriate amount of RE211 are mixed, are ground and calcined for a plurality of times, are pressed into a precursor piece, the corresponding long strip REBCO membrane is arranged on the top part of the precursor piece to serve as the seed crystal, and the REBCO bulk material is prepared by a melt textured method. The method is simple, improves the production efficiency of the bulk material, and ensures that the high temperature superconducting REBCO bulk material with a large single crystal domain structure is grown at a high speed on the conditions that impurity is free and crystal lattices are matched completely.

Description

technical field [0001] The invention relates to a method for high-speed growth of a superconducting bulk material from a 45° rare earth barium copper oxide thin film seed crystal, in particular to a REBCO (rare earth barium copper oxide) film with a 45° tetrasymmetric structure using a melt texture method. ) film as a seed crystal, a method for homogeneous high-speed epitaxial growth of superconducting bulk materials. Background technique [0002] Melt texturing (MTG) is generally considered to be a very promising method for the preparation of REBCO high temperature superconducting bulk materials. The resulting bulk materials have many potential applications, such as magnetic levitation forces, magnetic bearings, flywheel energy storage, and permanent magnets. At the application level, the requirements for bulk materials are generally larger in size and higher in critical current density (J c ), therefore, it is required to achieve a large single-domain structure and good ...

AI Technical Summary

Problems solved by technology

In general, as far as seeds have been reported to be used, there is no one that fully meets all the requirements.

In addition, in order to realize the preparation of large single-domain bulk materials, it is first necessary to obtain as large a seed crystal as possible to ensure the effective volume of the monodomain grown by epitaxial growth; The main axis direction of the lattice structure (, direction), the epitaxial growth rate of the bulk material is relatively slow, and it will take a long time to obtain a large volume, which is unfavorable for the preparation

Some research groups have used the method of placing multiple small seeds at the same time and changing the growth process to increase the corresponding growth rate and obtain an approximate single-domain structure, but this method greatly increases the complexity of the process and reduces the success rate