臺灣博碩士論文加值系統

中文摘要

　　雙相不�袗�的電化學性質，例如極化曲線等，是兩相綜合之表現，其個別單相性質及其測定方法是很值得探究的。本研究即以雙相結構之材料，如2205雙相不�袗�為對象，嘗試建立對各組成單相的電化學分析方法，並針對兩相分別在各溶液環境中之電化學性質進行探討。本研究利用選擇性溶解的方法，可以成功分離各單相而製作出2205雙相不�袗�個別相之試片。研究結果發現在2M H2SO4 + 0.5M HCl混酸水溶液中，2205雙相不�袗�在活性-鈍態轉換區的電位範圍中之兩個分離的陽極峰，確實是由沃斯田體相(Austenitic Phase, �� Phase)及肥粒體相(Ferritic Phase, �� Phase)個別的電化學反應貢獻所重疊而成。

　　在中性以及氧化性的酸溶液中，均沒有活性-鈍態轉換區陽極峰的出現，而兩相的電化學行為差異則在於腐蝕電位有一相當大的差異，顯示兩相在測試溶液中的電化學特性不同。此外我們經由開路電位測試，發現在氧化性的HNO3溶液中，兩相的極性與在中性以及還原性的溶液中有相反的現象。經伽凡尼電流量測確認，若定義電流由�悇蛝g導線流向�蚻菗陞縝V，則在還原性的H2SO4/HCl混酸溶液中，測定所得之值為負，此時�悇菗偉孚央A�蚻菗偃捧央C反之在氧化性的HNO3溶液中，測定所得之值為正，�悇菗偃捧央A�蚻菗偉孚央C

　　另外本研究利用已知2205雙相不�袗�於2M H2SO4 + 0.5M HCl中，於不同電位時，具有選擇性解的特性，將2205雙相不�袗�在選定的溶液組成以及電位下，進行長時間定電位蝕刻，成功地將其中一相完全溶解，此結果可嘗試用來製作微米級的網狀以及線狀元件，而使選擇性溶解的方法在微米級加工或元件製作上有所發揮。

Abstract

　The electrochemical behavior of duplex stainless steel (DSS), such as potentiodynamic polarization curve for example, is the properties mixed by the constituent phases. It is worth to explore the measuring methods and the electrochemical behavior of the constituent phases in 2205 DSS. The electrochemical behaviors of the constituent phases in 2205 DSS and the measuring methods of them were performed in this research. The selective dissolution method was employed to separate the constituent phases, and the constituent phase samples were successfully produced. It was found that the two anodic peaks in active-to-passive transition range is the superposition result of the electrochemical reactions of austenite (��) and ferrite (��) phases.

　No anodic peaks and active-to-passive regions were found in neutral NaCl and oxidizing HNO3 solutions, but the large difference in corrosion potential between �� and �� phase did exist. It means that the electrochemical behaviors are different between �� and �� phase in these solutions. However, according to the open circuit potential (OCP) tests, the polarity between �� and �� phases in HNO3 was found inverse to it in H2SO4/HCl. We define the current flow from �� to �� phase through instrument is positive. According to Galvanic current measurements, the value measured is negative in H2SO4/HCl mixed acidic solution, showed the anode is a phase, and the cathode is g phase. On the contrary, the value measured is positive, and the polarity is inversed.

　Finally, the well-known selective dissolution characteristics of 2205 DSS were employed to produce micro-scale devices. The long-term potentiostatic etching method was employed to dissolve the phase unwanted and the micro-mesh and micro-wire can be successfully produced.

總目錄

中文摘要............................................................................................................I
Abstract...........................................................................................................III
總目錄..............................................................................................................V
表目錄..........................................................................................................VIII
List of Tables………………………………...................................................IX
圖目錄..............................................................................................................X
List of Figures…………………………………………………..........……XIV
第一章 前言……………………………………………………….......……1
第二章 相關理論及文獻回顧……………………………………….......…4
2-1雙相不�袗�簡介.....................................................................................4
2-2 2205雙相不�袗�之兩相間優選腐蝕行為研究...…………….......…..5
2-3 2205雙相不�袗�之各組成相電化學性質相關研究............................8
第三章 實驗方法與步驟...............................................................................9
3-1 2205雙相不�袗�中各組成相之電化學性質研究................................9
3-1-1 實驗材料......................................................................................9
3-1-1-1 2205雙相不�袗�之金相觀察...............................................9
3-1-2 試片準備....................................................................................10
3-1-2-1 2205雙相不�袗�之雙相電化學試片製備..........................10
3-1-2-2 2205雙相不�袗�之動電位極化測試..................................11
3-1-2-3 定電位試驗、金相觀察以及相鑑定...................................11
3-1-2-4 2205雙相不�袗�各組成相之電化學試片製備..................12
3-1-2-5 2205雙相不�袗�各組成相之電化學測試..........................12
3-1-2-6兩相偶合之伽凡尼電流量測...............................................13
3-2 微米級網狀及柱狀結構體之製作......................................................13
3-2-1試片準備....................................................................................14
3-2-2 較長時間之定電位蝕刻及金相觀察......................................14
第四章 結果與討論.....................................................................................19
4-1 2205雙相不�袗�的性質......................................................................19
4-1-1 金相觀察以及成分分析............................................................19
4-1-2 雙相試片之電化學測試............................................................19
4-2 單相試片之製作結果..........................................................................20
4-3 各單相之電化學性質..........................................................................21
4-3-1 硫酸/鹽酸水溶液.....................................................................21
4-3-1-1 活性-鈍態轉換區..............................................................22
4-3-1-2 硫酸/鹽酸水溶液濃度的影響..........................................23
4-3-2 氯化鈉水溶液..........................................................................26
4-3-3 硝酸/氯化鐵水溶液.................................................................27
4-4 伽凡尼電流之量測..............................................................................28
4-5 微米級元件之製作..............................................................................29
第五章 結論.................................................................................................65
第六章 參考文獻.........................................................................................66

表目錄

表4-1 2205雙相不�袗�成分表.....................................................................32
表4-2經1100℃/30 min固溶處理之2205雙相不�袗�之�悇菑��蚻�
之EDS化學組成分析.........................................................................33
表4-3 2205雙相不�袗�及其單相試片在2 M H2SO4 + 0.5 M HCl中
，陽極之活性-鈍態轉換區電流峰電位值、腐蝕電位值及開路
電位之比較..........................................................................................34
表4-4 H2SO4/HCl水溶液濃度對陽極峰電位的影響...................................35

List of Tables

Table 4-1 Chemical composition of 2205 DSS used (wt %)...........................32

Table 4-2 Chemical compositions of �� and �� phases after 1100℃/
30 min solution treatment in 2205 DSS, analyzed by EDS
(wt %)..............................................................................................33

Table 4-3 The values of Ecorr, OCP, E�峿ax, and E�莪ax of 2205 DSS
and it’s constituent phases in 2 M H2SO4 + 0.5 M HCl...................34

Table 4-4 Effects of H2SO4/HCl concentration on the magnitude
of E�峿ax and E�莪ax...........................................................................35

圖目錄

圖3-1 試片示意圖(a)動電位極化測試試片(b)用於製備微米級結構
體之試片.............................................................................................16
圖3-2 單相試片製備構想示意圖(a)2205雙相不�袗�原材(b)將其中
一相大量溶解(c)以冷鑲埋用環氧樹脂再填補覆蓋(d)研磨使
試片單相暴露.....................................................................................17
圖3-3 伽凡尼電流量測裝置示意圖.............................................................18
圖4-1 2205雙相不�袗�經1100℃/30min固溶處理後水淬，並經95
℃之改良式 Murakami 溶液蝕刻5分鐘所呈現之金相……........ 36
圖4-2 2205雙相不�袗�分別於1.5 M HNO3、1 M NaCl以及2 M
H2SO4 + 0.5 M HCl水溶液中之動電位極化測試結果比較，
掃描速率為1 mV/sec..........................................................................37
圖4-3 2205雙相不�袗�在2 M H2SO4 + 0.5 M HCl之混酸水溶液中
，以-265 mVSCE之電位進行30分鐘之定電位試驗金相以及
其兩相個別之EDS化學組成分析.....................................................38
圖4-4 2205雙相不�袗�在2 M H2SO4 + 0.5 M HCl之混酸水溶液中
，以-330 mVSCE之電位進行30分鐘之定電位試驗金相以及
其兩相個別之EDS化學組成分析.....................................................39
圖4-5 2205雙相不�袗�之�悇蛦甈蛝掑�(a)試片巨觀形貌，(b)圖
4-5(a)中A點之SEM影像圖，(c)圖4-5(a)中B點之SEM
影像圖，(d)圖4-5(a)中C點之SEM影像圖........................................40
圖4-6 2205雙相不�袗�之�悇蛦甈蛝掑鑭EM形貌。(a)、(b)、(c)
不同倍率之觀察顯示環氧樹脂能夠填入大小不一的孔隙，
(d)為未經過環氧樹脂填充孔隙之試片.............................................41
圖4-7 2205雙相不�袗�在2 M H2SO4 + 0.5 M HCl之混酸水溶液
中，活性-頓態轉換區雙電流峰現象之解析示意圖(linear
scale)..................................................................................................42
圖4-8 2205雙相不�袗�之�悇菕B�蚻菪H及2205雙相不�袗�於2 M
H2SO4 + 0.5 M HCl之動電位極化曲線在活性-鈍態轉換區
試驗結果的比較..................................................................................43
圖4-9 2205雙相不�袗�及�悇菕B�蚻萓b2 M H2SO4 + 0.5 M HCl中
的開路電位量測數據之比較..............................................................44
圖4-10 �悇菕B�蚻萓b2 M H2SO4以及2 M H2SO4 + 0.1 M HCl中動
電位極化測試結果之比較.................................................................45
圖4-11 �悇菕B�蚻萓b0.5 M HCl以及0.5 M H2SO4 + 0.5 M HCl中
測試結果之比較.................................................................................46
圖4-12 �悇萓b固定鹽酸濃度為0.5 M，改變硫酸濃度之溶液中進
行動電位極化測試結果之比較........................................................47
圖4-13 �悇萓b固定硫酸濃度為2 M，改變鹽酸濃度之溶液中進行
動電位極化測試結果之比較...........................................................48
圖4-14 �蚻萓b固定鹽酸濃度為0.5 M，改變硫酸濃度之溶液中進
行動電位極化測試結果之比較.......................................................49
圖4-15 �蚻萓b固定硫酸濃度為2 M，改變鹽酸濃度之溶液中進行
動電位極化測試結果之比較...........................................................50
圖4-16 �悇菕B�蚻菪H及2205雙相不�袗�在1 M NaCl水溶液中之
動電位極化測試結果比較...............................................................51
圖4-17 �悇菕B�蚻菪H及2205雙相不�袗�在1 M NaCl水溶液中之
開路電位測試結果比較...................................................................52
圖4-18 �悇菕B�蚻菑�2205雙相不�袗�在1.5 M HNO3中動電位極
化測試結果比較...............................................................................53
圖4-19 �恁B�蚻菑�2205雙相不�袗�在1.5 M HNO3中之開路電位
測試結果...........................................................................................54
圖4-20 2205雙相不�袗�及�恁B�蚻萓b1.5 M HNO3 + 0.1 M FeCl3
的極化測試結果比較.......................................................................55
圖4-21 2205雙相不�袗�及�恁B�蚻萓b1.5 M HNO3 + 0.5 M FeCl3
的極化測試結果比較.......................................................................56
圖4-22 2205雙相不�袗�在1.5 M HNO3、1.5 M HNO3 + 0.1M
FeCl3及1.5 M HNO3 + 0.5M FeCl3 中之動電位極化測試
結果比較...........................................................................................57
圖4-23 �悇萓b1.5 M HNO3以及分別添加了0.1、0.5 M FeCl3中
之動電位極化測試結果之比較.......................................................58
圖4-24 �蚻萓b1.5 M HNO3以及分別添加了0.1、0.5 M FeCl3中之
動電位極化測試結果之比較...........................................................59
圖4-25 �悇菑��蚻萓b1.5M HNO3以及2M H2SO4 + 0.5M HCl中偶
合之伽凡尼電流量測結果...............................................................60
圖4-26 將�悇菑j量溶解後所得之SEM形貌，試片厚度約為40
�慆，蝕刻時間約11小時，部分位被溶解的�悇菑暑P��
相相連...............................................................................................61
圖4-27 將�蚻蛓X乎完全溶解後所得之SEM形貌，試片厚度約
為10�慆，蝕刻時間約為3小時........................................................62
圖4-28 在E�峿ax定電位之試片，在��/�蚻菗阞�近之�悇菪W陷較深
，顯示此處之�悇菬膃雩�大的溶解速率...........................................63
圖4-29 在E�莪ax定電位之試片，在��/�蚻菗阞�近之�悇袺銢犰釧�
顯的刃狀突起....................................................................................64

List of Figures

Fig. 3-1 The schematic graphs of samples used to perform (a) potentiodynamic polarization test and (b) micro-machining process...........................................................................................16

Fig. 3-2 The schematic diagrams of the respective constituent phase samples preparation processes. (a) 2205 DSS (b) one constituent phase was dissolved (c) the remaining space were filled with epoxy resin (d) ground the sample carefully could result in the exposure of only one constituent phase.........................................................17

Fig. 3-3 schematic diagram of the instrument for Galvanic current measurement...................................................................................18

Fig. 4-1 SEM micrograph of 2205 DSS, after 1100℃/30min solution treatment, etched with modified Murakami solution.......................36

Fig. 4-2 results of potentiodynamic polarization tests of the 2205 DSS in
1.5 M HNO3, 1 M NaCl and 2 M H2SO4 + 0.5 M HCl separately
(scan rate 1mV/sec)...........................................................................37

Fig. 4-3 The SEM micrograph and chemical composition of the 2205 DSS analyzed by EDS after potentiostatic polarization test (30 minutes) at -265mVSCE in 2 M H2SO4 + 0.5 M HCl.......................................38

Fig. 4-4 The SEM micrograph and chemical compositions of the 2205 DSS analyzed by EDS after potentiostatic polarization test (30 minutes) at -330mVSCE in 2 M H2SO4 + 0.5 M HCl...........................................39

Fig. 4-5 �� phase sample of 2205 DSS (a) macro-scale morphology, (b) SEM morphology of point A, (c) SEM morphology of point B, and (d) SEM morphology of point C in Fig. 4-5(a)......................................40

Fig. 4-6 The SEM micrographs of the �� phase in 2205 DSS. (a) 1000X, (b) 5000X, and (c) 2000X SEM micrographs reveal that the epoxy resin can fill the etched �� phase space. (d) the sample have not been filled with epoxy resin................................................................................41

Fig. 4-7 analysis of the active-to-passive transition of the 2205 DSS in 2 M H2SO4 + 0.5 M HCl (linear scale).....................................................42

Fig. 4-8 super positioned potentiodynamic polarization curves of the 2205 DSS in active-to-passive transition region in 2 M H2SO4 + 0.5 M HCl.....................................................................................................43

Fig. 4-9 The results of the open circuit potential measurements of 2205 DSS, �� and �� phases in 2 M H2SO4 + 0.5 M HCl.......................................44

Fig. 4-10 potentiodynamic polarization curves of �� and �� phases in 2 M H2SO4 and 2 M H2SO4 + 0.1 M HCl separately..............................45

Fig. 4-11 potentiodynamic polarization curves of �� and �� phases in 0.5 M HCl and 0.5 M H2SO4 + 0.5 M HCl separately.......................................46

Fig. 4-12 potentiodynamic polarization curves of �� phase in X M H2SO4 + 0.5 M HCl. X=0, 0.5, 1.0, 1.5, 2.0.........................................................47

Fig. 4-13 potentiodynamic polarization curves of �� phase in 2 M H2SO4 + Y M HCl. Y=0, 0.1, 0.3, 0.5................................................................48

Fig. 4-14 potentiodynamic polarization curves of �� phase in X M H2SO4 + 0.5 M HCl. X=0, 0.5, 1.0, 1.5, 2.0.........................................................49

Fig. 4-15 potentiodynamic polarization curves of �� phase in 2 M H2SO4 + Y M HCl. Y=0, 0.1, 0.3, 0.5................................................................50

Fig. 4-16 potentiodynamic polarization curves of the 2205 DSS, ���nand �� phases in 1 M NaCl.........................................................................51

Fig. 4-17 results of the open circuit potential measurements of the 2205 DSS, �� and �� phases in 1 M NaCl............................................................52

Fig. 4-18 potentiodynamic polarization curves of 2205 DSS, �� and �� phases in 1.5 M HNO3...................................................................................53

Fig. 4-19 results of the open circuit potential measurements of 2205DSS, �� and �� phases in 1.5 M HNO3...........................................................54

Fig. 4-20 potentiodynamic polarization curves of 2205DSS, �� and �� phases in 1.5 M HNO3 + 0.1 M FeCl3..........................................................55

Fig. 4-21 potentiodynamic polarization curves of 2205DSS, �� and �� phases in 1.5 M HNO3 + 0.5 M FeCl3..........................................................56

Fig. 4-22 potentiodynamic polarization curves of the 2205 DSS in 1.5 M HNO3, 1.5 M HNO3 + 0.1M FeCl3, and 1.5 M HNO3 + 0.5M FeCl3 separately........................................................................................ 57

Fig. 4-23 potentiodynamic polarization curves of �� phase in 1.5 M HNO3, 1.5 M HNO3 + 0.1 M FeCl3 and 1.5 M HNO3 + 0.1 M FeCl3 separately.........................................................................................58

Fig. 4-24 potentiodynamic polarization curves of �� phase in 1.5 M HNO3, 1.5 M HNO3 + 0.1 M FeCl3 and 1.5 M HNO3 + 0.1 M FeCl3 separately..........................................................................................59

Fig. 4-25 Galvanic current measurement of coupled �� and �� phases in A: 1.5M HNO3, and B: 2M H2SO4 + 0.5M HCl...................................60

Fig. 4-26 The SEM micrograph of the �� phase etched 2205 DSS. The etching time is 11 hours and there is still some retained �� phase connected to the �� phase. The thickness of the sample is 40�慆...............................................................................................61

Fig. 4-27 The SEM micrograph of the �� phase etched 2205 DSS. The etching time is 3 hours and the �� phase was almost dissolved. The thickness of the sample is 10�慆....................................................................62

Fig. 4-28 The SEM micrograph of the 2205 DSS potentiostatic etched at E�峿ax. The �� phase has greater dissolution rate near the ��/�� phase boundary..........................................................................................63

Fig. 4-29 The SEM micrograph of the 2205 DSS potentiostatic etched at E�莪ax. The The �� phase has lower dissolution rate near the ��/�� phase boundary..........................................................................................64

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