臺灣博碩士論文加值系統

中文摘要

　　超導量子干涉元件(Superconducting Quantum Interference Device，簡稱SQUID)是目前所知最敏感的磁通偵測器，可偵測到10-14至10-15 Tesla的訊號，約為地磁十億分之一，其獨特的磁通與電壓的週期特性，使得SQUID已被使用在精密量測 ，成為微弱物理量如磁場、磁場梯度、電流、電壓、電阻、電感及磁化率等測量上最靈敏的感測元件。而本文利用渦電流(eddy current)檢測法配合線圈(coil)探頭與SQUID磁量計(magnetometer)對金屬導體進行非破壞性檢測(nondestructive evaluation)。
本實驗中我們自行設計研發整套系統，其內容包括杜爾瓶(Dewar)、屏蔽桶(magnetically shielding box)，與線圈的製作及特性量測等。
我們利用G-10等級的玻璃纖維(fiberglass)作為杜爾瓶的材料，因為他具有熱膨脹係數小與低溫不裂開的特性，所以加工成為我們系統中盛裝液態氮(liquid nitrogen)的保溫容器。
在屏蔽桶的製作上，我們使用mu-metal抵抗地磁與各種低頻的雜訊，並配合銅網與鋁板阻擋高頻的電磁波，讓我們的屏蔽效應達到高水準的要求。
為了增加系統的實用性與便利性，我們設計激發線圈(excitation coil)與感應線圈(pick-up coil)作為梯度計(gradiometer)探頭，而探頭可以遠離SQUID，只要將感應電流經由傳輸線傳回屏蔽桶內並讓二次激發線圈(input coil)產生磁場，讓SQUID感應，即可達到缺陷訊號的讀取。

ABSTRACT

SQUID （Superconducting Quantum Interference Device）is the most sensitive magnetometer now. It can detect the signal as small as 10-14 to 10-15 Tesla, which is one-billionth of terrestrial magnetism. Another, because of the unique properties of the voltage variation periodically with magnetic flux, SQUID has been applied in precision measurement, like the weak magnetic field, current, voltage, inductance, and magnetic susceptibility.
Based on the eddy current method, this work proposed the nondestructive evaluation of the metal conductor by using the combination of the transfer coil probe and SQUID magnetometer.
We developed all the experimental system including Dewar, magnetically shielding box, and coil. In Dewar, the G-10 fiberglass is used to manufacture the vacuum bottle of liquid nitrogen because of the property of thermal conductivity and non-metal to avoid the influence of the SQUID sensing.
In magnetically shielding box, mu-metal plate, copper net, and aluminum plate are used. The first is for anti- terrestrial magnetism and low frequency noise. The others are for isolating the electromagnetic wave of high frequency.
Besides, we designed excitation coil and pick-up coil as the gradiometer probe to detect the crack signal. Then the induced current in the gradiometer probe rebuilt the magnetic field inside the magnetically shielding box, which is sensed by SQUID. It has many advantages than the tradition method of the direct sensing by SQUID. For example, the active probe is more practical and convenient than the heavy and large Dewar with SQUID. And the sensitivity is improved due to no limitation of the space between SQUID and sample

目錄

封面內頁
簽名頁
授權書………………………………………………………………iii
中文摘要……………………………………………………………iv
英文摘要……………………………………………………………vi
誌謝………………………………………………………………….viii
目錄…………………………………………………………………ix
圖目錄………………………………………………………………xi

第一章　緒論
1.1 研究背景與動機.........................................................1
1.2 文獻回顧.....................................................................2
第二章　實驗方法
2.1 渦電流檢測法.............................................................3
2.2 實驗設計與架構.........................................................6
第三章 系統設計
3.1 杜爾瓶.........................................................................8
3.2 超導量子干涉元件...................................................14
3.2.1 探針(Preobe)設計............................................16
3.3屏蔽系統....................................................................21
3.3.1 屏蔽桶屏蔽係數量測......................................25
3.4 探頭系統...................................................................30
3.4.1 平面式線圈梯度計原理與製作......................31
3.5 量測系統與人機介面................................………...44
3.5.1 二維滑軌平台(X-Y table)............................45
3.5.2 LabVIEW 人機介面..........................................46
第四章 實驗結果與討論…………………………………………..48
第五章 結論……...............................................................52
參考文獻..........................................................................................53
圖目錄

圖2.1 線圈磁場及感應磁場作用圖………………………………5
圖2.2 軸向式SQUID梯度計應用於非破壞性檢測示意圖……..5
圖2.3 NDE實驗架構圖………………………………………….7
圖3.1 杜爾瓶構造……………………………………….………..10
圖3.2 G-10管壁均勻塗佈機械裝置…………………………....10
圖3.3 G-10板均勻塗佈機械裝置……………………………....11
圖3.4 塗佈裝置作動示意圖……………………………………...11
圖3.5 Dewar設計圖……………………………………………..12
圖3.6 溫度計光罩...………………………..…………………..…12
圖3.7 溫度計校正曲線…………………………………………...13
圖3.8 超導體組成SIS幾何形狀的約瑟芬元件…………………17
圖3.9 兩個約瑟芬元件並聯組成SQUID………………………..17
圖3.10 SQUID等效電路………………………………………..18
圖3.11 SQUID外加偏壓電流…………………………………...18
圖3.12 SQUID用來作為磁廠量測的電子電路………………...19
圖3.13 一階軸向式梯度線圈……………………………………..19
圖3.14 平面式Gradiometer示意圖………………………………20
圖3.15 探針(Probe)………………………………………………..20
圖3.16 屏蔽桶架構圖……………………………………………..23
圖3.17 屏蔽桶材料結構…………………………………………..23
圖3.18 mu-metal水刀……………………………………………24
圖3.19 屏蔽桶實體………………………………………………...24
圖3.20 屏蔽係數量測系統示意圖...………………………………..27
圖3.21 外加磁場位於屏蔽桶左側與下方……………………….…27
圖3.22 外加磁場位於左方時的屏蔽係數………………………….28
圖3.23 外加磁場位於下方時的屏蔽係數………………………….29
圖3.24 雙D型激發線圈置於SQUID下方感測渦電流……….…34
圖3.25 Transfer coil電路示意圖……….……………………….…34
圖3.26 Transfer coil應用於心磁量測系統.…………………….…35
圖3.27 直接將imput coil置於液態氮中…………………….……36
圖3.28 不同直徑Pick-up coil與input coil訊號強度對照………37
圖3.29 Pick-up coil與input coil有效面積比與輸出功率..…..…38
圖3.30 量測共振頻率設備架構圖…………………………….……39
圖3.31 Transfer與SQUID的共振頻率……………………...……40
圖3.32 線圈探頭電流迴路圖………………………………….……40
圖3.33 探頭線圈示意圖與實體圖…………………………….……41
圖3.34 探頭線圈框架設計圖……………………………….………41
圖3.35 線磁場垂直分量B與其梯度變化量G位置變化分布….…42
圖3.36 線圈探頭掃描缺陷示意圖…………………………….……42
圖3.37 鎖相放大器量測原理示意圖………………………….……43
圖3.38 二維掃描平台實體圖……………………………….………45
圖3.39 LabVIEW人機界面..……………………………….………47
圖4.1 一維掃描缺陷示意圖……………………………...…………50
圖4.2 探頭經過缺陷時的電壓變化……………………...…………50
圖4.3 不同深度下感應磁場與頻率關係變化圖........……………...51

參考文獻

[1] John P. Wikswo, Jr., “SQUID Magnetometers for Biomagnetism andNondestructive Testing: Important Questions and Initial Answers,” IEEE Trans.Appl. Supercond., vol. 5, No. 2, pp. 74-120,1995.
[2] H. Fukutomi, T. Takagi, and M. Nishikawa, “Remote field eddy current techniqueapplied to non-magnetic steam generator tubes,” NDT&E International, vol. 34, pp. 17-23, 2001.
[3] C. Rem, E. M. Beunder, and A. J. van den Akker, “Simulation of Eddy-CurrentSeparators,” IEEE Trans. on Magnetics, vol. 34, no. 4, pp. 2280-2286, 1998.
[4] 劉福順，湯明，無損檢測基礎，北京航空航天大學，2002。
[5] 王仲生，無損檢測診斷現場實用技術，北京：機械工業出版，2002。
[6] Yoshihiro Nonaka, “A Double Coil Method for Simultaneously Measuring theResistivity, Permeability, and Thickness of a Moving Metal Sheet,” IEEE Trans.Inst.& Measurement, vol. 45, no. 2, pp. 478-482, 1996.
[7] A.Likhachev, V.Polushkin, S.Uchaikin, and B.Vasiliev, Supercond. Sci.Technol.3,148 (1990).
[8] 李家傳，陳積懋，無損檢測手冊，北京：機械工業出版，2002。
[9] C. C. Tai, J. H. Rose, and J. C. Moulder, “Thickness and Conductivity of MetallicLayers from Pulsed Eddy Current Measurements,” Rev. Sci. Instrum,vol. 67, pp. 3965-3972, 1996.
[10] W. G. Jenks, S. S. H. Sadeghi, and J. P. Wikswo, Jr., “SQUIDs for Non-DestructiveEvaluation,” J. of Physics D: Appl. Phys., vol. 30, pp. 293-323, 1997.
[11] 李冠勳,“差動式渦電流探頭於缺陷偵測之最佳激發頻率研
究”,國立台北科技大學製造科技研究所碩士論文,2005
[12] J. B. Hull, and V. B. John, Non-destructive testing, London: MacMillanEducation LTD., 1988.
[13] H. Weinstock, “A review of SQUID magnetometry applied to nondestructive evaluation”, IEEE Trans. Mag., vol. 27, no. 2, pp. 3231-3236, 1991.
[14] 鄭振宗,“直流高溫超導SQUID的特性及其在非破壞性檢測
上之應用”,國立台灣師範大學物理研究所博士論文,2001
[15] W G Jenksy, S S H Sadeghiz and J P Wikswo Jry, “REVIEW ARTICLESQUIDs for nondestructive evaluation”, J. Phys. D: Appl. Phys. 30,pp. 293–323, 1997.
[16] 物理會刊， 5 卷4 期, P.189-193 (1984)
[17] 楊謝樂, “Fabrication And Characterization of High-TC YBa2Cu3Oy Josephson Junction And SQUIDs”,國立台灣師範大學物理研究所博士論文,1999
[18] 物理雙月刊,24卷5期,P652-665,2002 年10 月
[19] 徐智魁,“高溫超導量子干涉元件一階梯度計之製作與特性研究”,國立台灣師範大學光電科技研究所碩士論文,2005


[20] J. T. Jeng, H. E. Horng, and H. C. Yang, “High-Tc SQUID magnetometers andgradiometers for NDE application,” Physica C, vol. 368, pp. 105-108, 2002.
[21] Jen-Tzong Jeng, Guan-Shiun Lee, Hsin-Chin Hung, Ju-Chien Chen, Wen-SungChiou, Li-Lun Chen, Ji-Cheng Chen, Chiu-Hsien Wu, Hong-Chang Yang, and H. E.Horng, Proc. of 6th European Conference on Applied Superconductivity(EUCAS 2003), Sorrento, 2003.
[22] Tadayuki Kondo and Hideo Itozaki, “Normal conductingtransfer coil forSQUID NDE”, Supercond. Sci. Technol. 17.pp 459–462, 2004.
[23] Akihiko KANDORI, Daisuke SUZUKI, Koichi YOKOSAWA, Akira TSUKAMOTO,Tsuyoshi MIYASHITA, Keiji TSUKADA and Kazumasa TAKAGI, “A Superconducting Quantum Interference Device Magnetometer with a Room-Temperature Pickup Coil for Measuring Impedance Magnetocardiograms”,
Jpn. J. Appl. Phys. Vol. 41 ,pp. 596–599, 2002.
[24] D F He ,H Itozaki and M Tachiki1,“Improving the sensitivity of a high-Tc SQUID at MHz frequency using a normal metal transformer”, Supercond. Sci. Technol. 19, S231–S234, 2006.