Method for polymer-assistant depositing high temperature superconducting coating conductor superconducting layer

Abstract

A macromolecule-assisted method of deposition for a superconducting layer of a high-temperature superconductivity coating electrical conductor has the preparation method as follows: a. dissolving rare-earth acetate, barium acetate and cupric acetate in monoprop with a stoichiometric proportion that rare-earth: barium: cupric equals to 1:2:3 to acquire a precursor solution; b. adding PVB, PEG or PVP into the precursor solution with the weight ratio of 2-8:100 to acquire a coating colloid; c. coating the coating colloid on a substrate and heating for drying; d. placing the substrate in a tubular furnace to carry out decomposition heat treatment; e. rapidly heating up the furnace temperature to 800-900 DEG C under moist argon atmosphere for 5-15min, then lowering the temperature to 750-780 DEG C for 1-3 hours, and then lowering the temperature to 350-500 DEG C under the argon atmosphere for low temperature oxygen-permeation annealing treatment, and the superconducting layer is acquired by cooling. The method has the advantages of low cost and simple technique, which is applied to industrialized production; the superconducting layer prepared is characterized by high biaxial texture, flat and dense surface and good superconductivity.

Description

technical field [0001] The invention relates to a method for preparing a high-temperature superconducting material, in particular to a method for preparing a superconducting layer of a high-temperature superconducting coated conductor. Background technique [0002] In 1986, the discovery of a new high-temperature superconducting material, yttrium barium copper oxide (YBCO), raised the superconducting transition temperature Tc from the original 30K to above 90K, and achieved a major breakthrough in the application of superconducting materials above the liquid nitrogen temperature. This important discovery opens up a new era not only in the theory of solid-state physics, but also in the potential application of high-temperature superconducting materials. However, due to the weak connection problem of the grain boundary of the YBCO bulk material itself, it directly affects the increase of the superconducting critical current density under the magnetic field, thus limiting the p...

AI Technical Summary

Problems solved by technology

The disadvantages are: the required equipment is expensive, and it is difficult to realize the large-scale commercial application of coated conductors

However, there are the following deficiencies in the existing preparation methods: in the metal-organic deposition method, polymer materials with a content of more than 20% are added, and the mass loss of the polymer compound during the decomposition and film formation process will lead to the formation of superconducting film surface A large number of holes and microcracks, which reduce the current-carrying performance of the superconducting layer

The surface of the film prepared by this phase formation process is relatively large and there are relatively many holes and microcracks. Such a surface microstructure also reduces the superconductivity of the film.

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