CN-121687642-B - Method for regulating and controlling residual resistance ratio of stable superconducting wire and superconducting wire

Abstract

The invention belongs to the technical field of superconducting wires, and relates to a method for regulating and controlling the residual resistance ratio of a stable superconducting wire and the superconducting wire. The invention provides a method for regulating and controlling the residual resistance ratio of a stable superconducting wire, which comprises the steps of presetting a target RRR value of the superconducting wire, carrying out cold working deformation and aging heat treatment on an NbTi/Cu superconducting composite ingot to obtain an NbTi/Cu superconducting bare wire, sequentially carrying out stretching, on-line annealing and cooling on the NbTi/Cu superconducting bare wire to obtain a superconducting bare wire to be processed, carrying out single-pass small-processing-amount deformation on the superconducting bare wire to be processed to reach a target size specification, and finally carrying out braiding insulation treatment to obtain a finished superconducting wire. According to the invention, through annealing and single-pass small-processing-amount deformation, the RRR value of the prepared finished superconducting wire can be regulated and controlled according to annealing parameters, and the uniformity of the size and the RRR value of the wire after molding is improved.

Inventors

• ZHANG KAILIN
• WANG RUILONG
• YAN GUO
• LIU XIANGHONG
• FENG YONG
• LI JIANFENG
• ZHANG PINGXIANG
• GUO QIANG
• HAN LUYANG
• LI HENGCHAO
• WANG BINGYU
• ZHAO JIAJUN
• FAN XUDONG
• ZHU YANMIN
• ZHOU ZIJING

Assignees

• 西安聚能超导线材科技有限公司

Dates

Publication Date

20260505

Application Date

20260209

Claims (10)

1. 1. A method for regulating and controlling the residual resistance ratio of a stable superconducting wire is characterized by comprising the steps of presetting a target RRR value of the superconducting wire; the NbTi/Cu superconducting composite ingot is subjected to cold working deformation and aging heat treatment to prepare NbTi/Cu superconducting bare wire; Sequentially stretching, on-line annealing and cooling the NbTi/Cu superconducting bare wire to obtain a superconducting bare wire to be processed, wherein the RRR value of the superconducting bare wire to be processed is 20-50 higher than the target RRR value; And deforming the superconducting bare wire to be processed to reach a target size specification through single-pass small processing amount, and finally performing braiding insulation treatment to obtain a finished superconducting wire, wherein the absolute difference between the RRR value of the finished superconducting wire and the target RRR value is not more than 15.
2. 2. The method for regulating and controlling the residual resistance ratio of a stable superconducting wire rod according to claim 1, wherein the machining rate of the single-pass small-machining-amount deformation is 3-10%.
3. 3. The method for regulating and stabilizing the residual resistance ratio of a superconducting wire according to claim 1, wherein the temperature of the on-line annealing is 300-600 ℃ and the processing speed is 50-120 m/min.
4. 4. The method for regulating and controlling the residual resistance ratio of a stable superconducting wire according to claim 1, wherein the length of the on-line annealing is 1-3 m.
5. 5. The method for controlling and stabilizing the residual resistance ratio of the superconducting wire according to claim 1, wherein the NbTi/Cu superconducting composite ingot is subjected to extrusion, drawing, aging heat treatment and twisting in sequence to prepare the NbTi/Cu superconducting bare wire.
6. 6. The method for controlling and stabilizing the residual resistance ratio of a superconducting wire according to claim 1, wherein the pass processing rate of the drawing is 10-30%.
7. 7. The method of controlling and stabilizing a residual resistance ratio of a superconducting wire according to claim 1, wherein the target dimension specification is a round wire of Φ0.5mm to Φ3.0 mm.
8. 8. The method of controlling a residual resistance ratio of a stable superconducting wire according to claim 1, wherein the target dimension specification is a flat wire of 0.8mm x 0.5mm x 3.0 mm.
9. 9. The method for regulating and controlling the residual resistance ratio of a stable superconducting wire according to claim 1, wherein the copper super ratio of the NbTi/Cu superconducting composite ingot is 0.6-20.0.
10. 10. An NbTi superconducting wire, characterized in that it is produced by the method for controlling and stabilizing the residual resistance ratio of the superconducting wire according to any one of claims 1 to 9.

Description

Method for regulating and controlling residual resistance ratio of stable superconducting wire and superconducting wire Technical Field The invention belongs to the technical field of superconducting wires, and relates to a method for regulating and controlling the residual resistance ratio of a stable superconducting wire and the superconducting wire. Background The NbTi superconducting wire has excellent superconducting performance, mechanical stability and cost advantages, and is widely applied to the high-end technical fields such as Magnetic Resonance Imaging (MRI), particle accelerators, controllable nuclear fusion and the like. The residual resistance ratio (RRR value) is used as a core index for representing the purity and conductivity of the copper matrix of the superconducting wire, and directly influences the thermal stability, quench recovery capability and overall operation reliability of the wire in a superconducting state, and the requirements of different application scenes on the RRR value are obviously different. However, in the existing preparation process of the NbTi superconducting wire, the RRR value of the superconducting wire is improved as much as possible mainly through various technical means, on one hand, the RRR value is large in dispersion and difficult to accurately match with target requirements, and on the other hand, the requirements of markets on customizing the RRR value superconducting wire cannot be met. Therefore, developing a preparation method capable of accurately regulating and stabilizing the RRR value of an NbTi superconducting wire rod, improving the uniformity of the wire rod size and simplifying the process flow becomes a key problem to be solved urgently in the technical field of the current superconducting wire rod. Disclosure of Invention In order to overcome the defects of the prior art, the invention provides a method for regulating and controlling the residual resistance ratio of a stable superconducting wire rod and the superconducting wire rod, wherein the target residual resistance ratio of the superconducting wire rod is selected through on-line annealing, and the target residual resistance ratio of the superconducting wire rod is fixed through single-pass small-processing-amount deformation after on-line annealing. The RRR value of the finished superconducting wire rod prepared by the technical scheme provided by the invention can be regulated and controlled according to the annealing parameters, and the dimensional uniformity of the wire rod after molding is improved. In one aspect, the present invention relates to a method of regulating and controlling the residual resistance ratio of a stable superconducting wire, comprising: Presetting a target RRR value of a superconducting wire; the NbTi/Cu superconducting composite ingot is subjected to cold working deformation and aging heat treatment to prepare NbTi/Cu superconducting bare wire; Sequentially stretching, on-line annealing and cooling the NbTi/Cu superconducting bare wire to obtain a superconducting bare wire to be processed, wherein the RRR value of the superconducting bare wire to be processed is 20-50 higher than the target RRR value; And deforming the superconducting bare wire to be processed to reach a target size specification through single-pass small processing amount, and finally performing braiding insulation treatment to obtain a finished superconducting wire, wherein the absolute difference between the RRR value of the finished superconducting wire and the target RRR value is not more than 15. The technical staff in the field can select different annealing parameters according to target RRR values of the NbTi/Cu superconducting bare wire and the finished superconducting wire to obtain the superconducting bare wire to be processed with different RRR values, and finally fix the RRR value of the finished superconducting wire through single-pass small processing amount, thereby achieving the purpose of preparing the finished superconducting wire with the required RRR value according to the requirement. Further, in the method for regulating and controlling the residual resistance ratio of the stable superconducting wire provided by the invention, the processing rate of the single-pass small processing deformation is 3-10%. Further, in the method for regulating and stabilizing the residual resistance ratio of the superconducting wire provided by the invention, the temperature of the on-line annealing is 300-600 ℃, and the processing speed is 50-120 m/min. Further, in the method for regulating and controlling the residual resistance ratio of the stable superconducting wire provided by the invention, the length of the on-line annealing is 1-3 m. Further, in the method for regulating and controlling the residual resistance ratio of the stable superconducting wire provided by the invention, the NbTi/Cu superconducting bare wire is prepared by sequentially extruding, drawing, aging heat trea