Method for joining second-generation high-temperature superconducting wires by melting diffusion

Abstract

The present invention relates to a welding method for a second generation high temperature superconducting wire including a substrate, a buffer layer, a superconductor layer, and a stabilizing material layer, wherein parts of the stabilizing material layers contained in two strands of the second generation high temperature superconducting wire are removed, the superconductor layers of two strands of the second generation high temperature superconducting wire exposed by the removal of the stabilizing material layer abut each other and are heated to the melting point of the superconductor layer to melt-diffuse the abutting superconductor layers and weld two strands of the second generation high temperature superconducting wire together. Subsequently, the welded portion is oxygenation-annealed under an oxygen atmosphere to recover superconducting properties of the second high temperature superconducting wire. The above-described configuration of the present invention enables superconductor layers to directly abut each other and to be melt-diffused without using a mediator, thus producing a wire having a full length with a rare junction resistance as compared to a normal conduction junction method. Specifically, the present invention brings a partial oxygen pressure to a nearly vacuum state to lower the melting point, thereby enabling junction processes to be performed without melting a stabilizing material layer containing silver (Ag).

Description

technical field [0001] The invention relates to a method for joining a second-generation high-temperature superconducting wire including a substrate part, a buffer layer, a superconductor layer, and a stabilizing material layer, and in particular to a superconductor layer that directly butts and joins a second-generation high-temperature superconducting wire, so that It is a fusion-diffusion bonding method of the second generation of high-temperature superconducting wires that is connected into one strand by melt-diffusion under the regulation of oxygen partial pressure. [0002] The melt-diffusion bonding method of the second-generation high-temperature superconducting wires disclosed in the present invention controls the oxygen partial pressure to a state close to a vacuum to lower the eutectic melting point (eutectic melting point), and adjusts the butt joint of the second-generation high-temperature superconducting wires to perform melt-diffusion (melting diffusion) oxygen...

AI Technical Summary

Problems solved by technology

However, since it is necessary to perform heat treatment on the entire joint portion of the produced high-temperature superconducting wire, the stabilizing material layer 14 laminated on the second-generation high-temperature superconducting wire may be contaminated and deformed due to the high temperature generated by the heat treatment.

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