本文關鍵詞： 涂層導體 織構化基帶 定向電沉積 電化學拋光　出處：《西南交通大學》2015年碩士論文　論文類型：學位論文

【摘要】：YBCO等涂層導體的出現(xiàn)給高溫超導體的實用化路線開辟了嶄新的道路,涂層導體的結構由織構化基帶、過渡層和超導層組成,基帶作為載體,是決定超導材料性能的主要因素,考慮到現(xiàn)有的基帶制備工藝,金屬基帶的表面質量不能滿足涂層導體的要求,因此本文研究了一種提高Ni-5%W合金基帶表面質量的脈沖電化學拋光方法。另一方面,高昂的基帶制備成本是限制涂層導體大規(guī)模應用的主要障礙,因此我們希望利用電沉積技術,在無織構高強基帶上制備出滿足涂層導體外延生長需要的雙軸織構的金屬薄膜,則有可能開發(fā)出成本低廉的涂層導體織構化基帶制造技術,大大降低涂層導體的制造成本。研究內容主要有以下幾個方面：(1)采用脈沖電化學拋光工藝,研究不同脈沖參數(shù)即電流密度、脈沖頻率、脈沖占空比對NiW基帶的表面拋光效果的影響,通過掃描電鏡和原子力顯微鏡對拋光后的基帶表面微觀形貌進行表征,并根據(jù)測試結果,調整實驗參數(shù),尋找最佳的脈沖電化學拋光工藝,結果表明在合適的拋光工藝下可以獲得納米級粗糙度的基帶表面質量。(2)在鎳基帶上電沉積銅層。通過脈沖電化學拋光對金屬鎳基帶進行表面預處理獲得平整光滑的表面,探索在鎳基帶上電沉積制備連續(xù)致密銅層實驗最佳的電沉積工藝參數(shù),結果表明,在最佳電沉積工藝下可以制備連續(xù)致密完整的的銅薄膜,為后續(xù)銀薄膜的沉積提供好的過渡層。(3)在銅基帶上電沉積銀薄膜。通過脈沖電化學拋光方法對金屬銅基片進行表面改性,首先考察電鍍技術是否具有定向作用,并探討不同的脈沖工藝參數(shù)下,金屬鍍層的織構,尋找獲得(111)相對取向擇優(yōu)度最強的銀薄膜的實驗工藝參數(shù),結果表明電鍍確實具有定向作用,在合適脈沖參數(shù)下制備了連續(xù)致密(111)取向擇優(yōu)的銀薄膜,(4)用類似的定向電鍍原理性裝置在金屬基帶上沉積銀薄膜。通過選擇定向作用,制備出了具有(200)擇優(yōu)取向的雙軸織構的Cu/Ag復合基帶。(5)在雙軸織構化的鎳鎢基帶,通過化學沉積制備了具有(200)取向擇優(yōu)的Ag薄膜緩沖層。熱處理后,銅基片上沉積的Ag薄膜由(111)取向擇優(yōu)轉變?yōu)?200)取向擇優(yōu)。
[Abstract]:The appearance of coating conductors such as YBCO has opened a new way for the practical route of high temperature superconductors. The structure of coating conductors is composed of textured baseband, transition layer and superconducting layer, which is the main factor that determines the properties of superconducting materials. Considering the existing substrate preparation technology, the surface quality of metal substrate can not meet the requirements of coated conductors. Therefore, a pulsed electrochemical polishing method to improve the surface quality of Ni-5%W alloy substrate is studied in this paper, on the other hand, The high cost of substrate preparation is the main obstacle to limiting the large-scale application of coated conductors. Therefore, we hope to use electrodeposition technology to prepare biaxial textured metallic films on the high strength substrate without texture to meet the requirements of epitaxial growth of coated conductors. It is possible to develop a low-cost fabrication technology for textured baseband of coated conductors, which greatly reduces the manufacturing cost of coated conductors. The main research contents are as follows: 1) Pulsed electrochemical polishing process is adopted. The effects of different pulse parameters such as current density, pulse frequency and pulse duty ratio on the surface polishing of NiW baseband were studied. The micromorphology of the polished baseband was characterized by scanning electron microscope and atomic force microscope. According to the test results, the experimental parameters are adjusted to find the best pulse electrochemical polishing process. The results show that the surface quality of nanoscale roughness can be obtained by electrodeposition of copper layer on nickel substrate under proper polishing process. The smooth surface is obtained by surface pretreatment of metal nickel base band by pulse electrochemical polishing. The optimum parameters for electrodeposition of continuous dense copper layer on nickel substrate were explored. The results showed that continuous dense and complete copper films could be prepared under the optimum electrodeposition process. To provide a good transition layer for the subsequent deposition of silver films, silver films were electrodeposited on copper substrates. Surface modification of metallic copper substrates was carried out by pulse electrochemical polishing. At the same time, the texture of metal coating under different pulse process parameters is discussed, and the experimental technological parameters of silver film with the strongest relative orientation preference are obtained. The results show that the electroplating does have directional effect. In this paper, a continuous dense silver thin film with preferred orientation has been prepared under suitable pulse parameters. Silver thin films have been deposited on metal substrates using a similar directional electroplating device. In this paper, the Cu/Ag composite substrate with biaxial texture with #number0#) orientation was prepared. The Ni-W substrate with biaxial texture was prepared by chemical deposition. The Ag film buffer layer with the preferred orientation was prepared by chemical deposition. After heat treatment, the Ag film was prepared by chemical deposition. The Ag thin films deposited on copper substrates have a preferred orientation from 111) to 200).
【學位授予單位】：西南交通大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TQ153

【參考文獻】

相關期刊論文 前3條

1 鄒金橋,盧建樹;YBCO涂層超導體的最新研究進展[J];表面技術;2003年01期

2 高菲;劉丹敏;劉星;郝斐;戴琳;周美玲;;在Ag基帶上用PLD法沉積YBCO超導薄膜的研究[J];低溫物理學報;2005年S1期

3 趙忠賢,陳立泉,楊乾聲,黃玉珍,陳賡華,唐汝明,劉貴榮,倪泳明,崔長庚,陳烈,王連忠,郭樹權,李山林,畢建清,王昌慶;液氮溫區(qū)的新氧化物超導體[J];科學通報;1987年11期

，

本文編號：1494309