nb based on layer-by-layer stacking 3 Al superconducting precursor wire preparation method

Abstract

A Nb based on layer-by-layer stacking 3 The preparation method of Al superconducting precursor wire mainly includes: A. Preparation of Nb-Al composite sheath: Nb foil and Al foil are alternately stacked in the rectangular groove of the tubular Nb box from bottom to top, and the upper cover is covered , in the Cu tube, welded and sealed; B. Preparation of Nb-Al single mandrel: the Nb-Al composite sheath is hydrostatically extruded, repeatedly drawn, and then corroded to remove the copper to obtain the Nb-Al single mandrel. Mandrel; C, Nb 3 Preparation of Al superconducting precursor wires: multiple Nb‑Al single mandrels are packed closely into Cu or Cu alloy sheaths, and multi-cores are obtained by electron beam sealing welding, hydrostatic extrusion, and repeated drawing. Wire rod; then corrode to remove copper. The method is simple to operate, the assembly filling rate of the foil material is high, and the compactness of each layer of foil material is uniform. The final superconducting wire prepared by it has good performance, strong consistency and high qualified rate. It is especially suitable for the preparation of long superconducting wires.

Description

technical field [0001] The invention belongs to the technical field of preparation methods of low-temperature superconducting materials, and in particular relates to a multi-core Nb 3 Preparation method of Al superconducting precursor wire. Background technique [0002] Nb 3 Al is the current superconducting transition temperature (T c ), critical current density (J c ) and upper critical field (H c2 ) and other low-temperature superconducting materials with the best comprehensive practical performance. it with Nb 3 Compared with Sn, the superconducting transition temperature reaches 19.3K, and it also belongs to the A15 structure intermetallic compound and grain boundary pinned superconductor; and has a higher upper critical field and better high-field critical current density characteristics; especially important, It is better than Nb 3 Sn has more excellent stress-strain tolerance characteristics. Therefore Nb 3 Al superconducting wires are considered to have gre...

AI Technical Summary

Problems solved by technology

The compound after winding is prone to problems such as large size deviation, low tube filling rate, and uneven lamination between layers.

In addition, the foils of each layer of the composite after winding are extruded, entangled, and pulled to form constraints, which are difficult to adjust in the later stage, which leads to uneven deformation of each component in subsequent processing. During the process, it is easy to have defects such as wire breakage and component segregation in the wire, which will eventually affect the performance of the superconducting wire.

As a result, it is difficult to process, the consistency of the product is poor, and the pass rate is low

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