CN-121988738-A - High-uniformity NbTi alloy for superconducting cable and preparation method thereof

Abstract

The invention belongs to the technical field of electrodeposition, and discloses a high-uniformity NbTi alloy for a superconducting cable and a preparation method thereof. The method comprises the steps of preparing choline chloride-urea deep eutectic solvent, respectively dissolving Nb source and Ti source to form two independent electrolytes, adopting an anodic aluminum oxide template to form an Nb nanowire core through electrochemical codeposition, then depositing a Ti shell to obtain a core-shell structure, dissolving the template, centrifugally cleaning to obtain Nb/Ti nano powder, and carrying out pressing and spark plasma sintering to obtain the NbTi alloy. The NbTi alloy prepared by the method has high uniformity, is suitable for the quantum signal transmission requirement of a superconducting cable, has stable and reliable process and has good application prospect.

Inventors

• ZHOU ZIJING
• YAN GUO
• LIU XIANGHONG
• FENG YONG
• LI JIANFENG
• ZHANG PINGXIANG
• GUO QIANG
• YAN PENGFEI
• AN JINCHAO
• ZHAO JIAJUN
• WANG RUILONG
• CHEN XIAO
• ZHU YANMIN
• ZHANG KAILIN

Assignees

• 西安聚能超导线材科技有限公司

Dates

Publication Date

20260508

Application Date

20260107

Claims (10)

1. 1. The preparation method of the high-uniformity NbTi alloy for the superconducting cable is characterized by comprising the following steps of: s1, preparing electrolyte, namely preparing a choline chloride-urea deep eutectic solvent, and respectively dissolving a Nb source and a Ti source in the deep eutectic solvent to form electrolyte containing Nb ions and Ti ions; s2, template pretreatment, namely adopting an electrochemical codeposition method, selecting an anodic aluminum oxide template, and depositing a layer of gold film on the surface of the template through a magnetron sputtering process to serve as a conductive substrate of a working cathode; S3, depositing the Nb nanowire core, namely placing the pretreated anodic aluminum oxide template in electrolyte containing Nb ions, and performing electrodeposition to form the Nb nanowire core in a pore canal of the anodic aluminum oxide template; S4, ti shell deposition and core-shell structure formation, namely taking out an anodic aluminum oxide template which is subjected to Nb nanowire core deposition, cleaning, transferring the anodic aluminum oxide template into electrolyte containing Ti ions, and performing electrodeposition to deposit Ti shells on the surfaces of the Nb nanowire cores to form an Nb/Ti core-shell structure; s5, template dissolution and nano powder acquisition, namely immersing the template deposited with the Nb/Ti core-shell structure into alkaline solution to dissolve an anodic aluminum oxide template, and collecting a reaction system precipitate to obtain Nb/Ti nano powder; And S6, pressing and sintering, namely performing pressing treatment on the Nb/Ti nano powder, and performing spark plasma sintering on the pressed blank to obtain the high-uniformity NbTi alloy for the superconducting cable.
2. 2. The preparation method according to claim 1, wherein in S1, the molar ratio of choline chloride to urea is 1:1.5-3.
3. 3. The method according to claim 1, wherein in S1, the Nb source is NbCl 5 , the Ti source is TiCl 4 ,NbCl 5 with a concentration of 0.05-0.2 mol/L, and the TiCl 4 with a concentration of 0.05-0.3 mol/L.
4. 4. The method according to claim 1, wherein in S2, the pore diameter of the anodized aluminum template is 80 to 120nm, the thickness is 30 to 100 μm, and the thickness of the gold film is 200 to 500nm.
5. 5. The method according to claim 1, wherein in S3, the deposition temperature is 60 to 100 ℃, the deposition time is 60 to 80min, and the deposition potential is-1.3 to-1.7V.
6. 6. The method according to claim 1, wherein in S4, the deposition temperature is 60 to 100 ℃, the deposition time is 70 to 90min, and the deposition potential is-1.4 to-1.8V.
7. 7. The preparation method according to claim 1, wherein in S5, the alkaline solution is a NaOH solution of 2 to 4 mol/L.
8. 8. The method according to claim 1, wherein in S6, the pressure of the pressing treatment is 100-800 MPa, the pressure maintaining time is 30-60S, the sintering temperature of the spark plasma is 1200-1600 ℃, the sintering time is 1-2 h, and the vacuum degree in the sintering process is not lower than 5.0X10 -3 Pa.
9. 9. A highly uniform NbTi alloy for a superconducting cable, characterized in that the highly uniform NbTi alloy for a superconducting cable is produced by the production method according to any one of claims 1 to 8.
10. 10. The high-uniformity NbTi alloy for superconducting cables according to claim 9, wherein the molar ratio of Nb element to Ti element is 4:6 to 5:5.

Description

High-uniformity NbTi alloy for superconducting cable and preparation method thereof Technical Field The invention belongs to the technical field of electrodeposition, and relates to a high-uniformity NbTi alloy for a superconducting cable and a preparation method thereof. Background The NbTi superconducting material has excellent superconducting performance, becomes a core conductor material of high-end devices such as a superconducting coaxial cable of a quantum computer and the like, and has irreplaceable application value in the field of quantum signal transmission. The signal transmission stability of the superconducting cable is closely related to the component uniformity of NbTi alloy, and the distribution of Nb and Ti elements in the alloy is required to be highly consistent so as to ensure the accuracy and reliability of quantum signal transmission. Currently, the preparation of NbTi alloys still faces technical challenges. Because the melting point difference of Nb and Ti is extremely large, the traditional smelting process is extremely easy to cause alloy component segregation, the uniform distribution of elements is difficult to realize, and only a few enterprises in the world can realize large-scale preparation. In order to improve component uniformity, various alternative processes such as electrodeposition and powder metallurgy are tried in the related field, but the problems that in a traditional aqueous solution electrodeposition system, metal ions such as Nb 3+、Ti3+ are poor in stability, hydroxide precipitation is easy to generate, the difference of ion deposition potential is large, and accurate control of co-deposition is difficult to realize are solved, the traditional ionic liquid can improve ion stability, is sensitive to air and moisture, has severe operation conditions and partial toxicity, and limits industrial application, and a deep eutectic solvent is used as a novel green solvent, and has the advantages of wide electrochemical window, good environmental stability and the like, but the system is large in viscosity, so that ion migration rate is slow, concentration polarization is obvious, and deposition efficiency and coating uniformity are influenced. In addition, the existing partial process adopts a single deposition mode or a complex additive system, so that not only is the proportion of Nb and Ti elements difficult to accurately regulate and control, but also impurities can be introduced or the process cost can be increased, and the prepared NbTi alloy is difficult to meet the severe requirement of a quantum computer superconducting cable on high uniformity. Along with the rapid development of quantum computing technology, the requirements on uniformity and stability of NbTi alloy for superconducting cables are continuously improved, and the limitation of the existing preparation process becomes a key bottleneck for restricting the performance breakthrough of related high-end devices. Therefore, the NbTi alloy preparation method which can accurately control components, promote alloy uniformity, has stable process and is environment-friendly is developed, and has important practical significance and urgent need for promoting the technical progress in high-end fields such as quantum computers and the like. Disclosure of Invention The invention aims to solve the core technical problems existing in the existing NbTi alloy preparation process, and specifically comprises the following steps: The traditional smelting process is extremely large in melting point difference between Nb and Ti, component segregation is easy to generate, even distribution of alloy elements is difficult to realize, severe requirements of superconducting cables on high uniformity cannot be met, in a traditional aqueous solution electrodeposition system, nb 3+、Ti3+ and other metal ions are poor in stability, hydroxide precipitates are easy to generate, auxiliary reagents such as complexing agents and stabilizers are required to be added, the process complexity and the environmental burden are increased, the difference of deposition potential is large, the co-deposition control difficulty is high, the traditional ionic liquid is sensitive to air and moisture, the operation condition is severe, part of ionic liquid and decomposition products thereof have toxicity, industrial application is limited, and the problems of high system viscosity, slow ion migration rate, obvious concentration polarization and the like exist in the traditional deep eutectic solvent electrodeposition technology, so that the deposition efficiency is low, the coating quality is poor, and the component proportion is difficult to accurately regulate when NbTi alloy is prepared. In order to solve the technical problems, the invention provides a high-uniformity NbTi alloy for a superconducting cable and a preparation method thereof, and the specific technical scheme is as follows: In a first aspect, the present invention provides a method