應用微量流動電解液於電化學線放電加工石英玻璃之研究

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郭寬淵(Kuan-yuan Kuo) 查詢紙本館藏

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機械工程學系

論文名稱

應用微量流動電解液於電化學線放電加工石英玻璃之研究
(Study of Wire Electrochemical Discharge Machining (WECDM) of Quartz Glass with Titrated Electrolyte Flow)

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摘要(中)

石英具有優異性質，但其硬脆特性，傳統加工方式很難在效率與精度二者兼顧，電化學放電加工是以高溫熔融並且蝕刻輔助加工，相當適合於石英材料，WECDM加工系統內絕緣氣膜結構控制不易及加工區域內電解液循環困難，因此，探討WECDM加工機制，開發新加工方式及改善微溝槽表面品質為本論文研究主題。
首先探討流動電解液對加工石英玻璃影響，及氣膜成形特性進行研究，實驗中以石墨粉末之導電特性，分散電化學放電之能量，提升加工後工件表面之精度。並進一步利用碳化矽粉之複合加工方式改善加工效率及精度。實驗結果顯示液滴法電化學放電線切割加工石英玻璃有良好效果，擴槽量及比直性均佳，但表面品質及精度卻無法有效控制。於電解液中加入石墨粉末或加入碳化矽，藉以達到控制精度及改善表面粗度。實驗結果顯示，在相同條件下未加入任何粉末之電解液WECDM加工其表面粗度值Ra＝1.13μm，在加入0.4wt％石墨於電解液時，表面粗度可達到Ra＝0.36μm，改善率為68％；在加入碳化矽5wt％於電解時，表面粗度可達到Ra＝0.22μm，改善率為80％，且在最適當條件下電解液用量極少。證明利用石墨或碳化矽粉之特性在滴定電解液中局部化加工石英玻璃，可有效改善表面品質及減少環境汙染、降低成本、達到1次加工減少加工工序等優點。

摘要(英)

Quartz has excellent properties, but its brittleness property results in the difficulty of balance between efficiency and precision for traditional machining method. ECDM aids in machining with high temperature fusion and etching, and is very appropriate for quartz material. In WECDM machining system, uneasy control of insulation gas film structure and difficult electrolyte circulation in machining zone. Therefore, thesis topic is to explore WECDM machining mechanisms, development new methods and improve the micro slit surface quality.
First, investigate the flow of electrolyte influence on the processing of quartz glass, adding graphite powder or silicon carbide powder of composite processing methods to improve the processing efficiency and accuracy. From experimental results, the surface roughness value for electrolyte WECDM machining without adding any powder under the same condition is Ra＝1.13μm, while the surface roughness may achieve Ra＝0.36μm as 0.4wt％ of graphite is added into electrolyte . The improvement rate is 68%. As 5wt％ of silicon carbide is added into electrolyte, the surface roughness can achieve Ra＝0.22μm, that is, the improvement rate is 80%. Furthermore, electrolyte is used very few under the best appropriate condition. It is proved that the utilization of graphite or silicon carbide characteristics for local machining of quartz glass in titration electrolyte is advantageous of improving surface quality effectively, reducing environmental pollution, lowering cost, and achieving one-time machining to reduce machining procedures.

關鍵字(中)

★ WECDM
★ 微溝槽
★ 石英玻璃
★ 滴定電解液
★ 表面粗糙度

關鍵字(英)

★ WECDM
★ Micro slit
★ Quartz glass
★ droplet titration
★ Surface Roughness

論文目次

目錄
摘要................................................................................................................i

Abstract.................................................................................................................ii

謝誌.............................................................................................................. v

目錄.............................................................................................................. iii

圖目錄............................................................................................................. vi

表目錄............................................................................................................. ix

第一章緒論.........................................................................................................1
1-1 研究動機.................................................................................................1
1-2 研究目的.................................................................................................3
1-3 文獻回顧.................................................................................................4
1-4 本論文之構成.........................................................................................9
第二章研究方法與原理...................................................................................10
2-1 電化學放電加工原理...........................................................................10
2-2 實驗方法與原理介紹...........................................................................15
第三章應用液滴滴定方法於電化學放電線切割加工石英玻璃之研究.......18
3-1 前言.......................................................................................................18
3-2 實驗設備與方法...................................................................................22
3-2-1 實驗設備....................................................................................22
3-2-2 實驗材料....................................................................................23
3-2-3 實驗原理與步驟........................................................................25
3-3 實驗流程...............................................................................................28
3-4 結果與討論...........................................................................................29
3-4-1液滴內流體流動對絕緣氣膜影響…………………………….29
3-4-1-1電解液與石英玻璃及銅線電極之液滴形成原因..................29
3-4-1-2線電極與液滴接觸距離變化對加工影響……………..........31
3-4-1-3液滴內氧氣泡與氫氣泡分佈對氣膜影響..............................34
3-4-1-4液滴內流體流動方向對加工影響..........................................35
3-4-2電壓對加工深度的影響……………………………………….37
3-4-3流量對加工的影響…………………………………………….40
3-4-4進給速度對加工的影響………………………….…………….42
3-4-5電解液流動方式對加工影響………………………………….45
3-5 結論.......................................................................................................53
第四章應用石墨粉加入電解液提升電化學放電加工性能之研究...............56
4-1 前言.......................................................................................................56
4-2 實驗設備與方法...................................................................................58
4-2-1 實驗設備....................................................................................58
4-2-2 實驗方法與原理........................................................................60
4-3 實驗流程...............................................................................................64
4-4 結果與討論...........................................................................................66
4-4-1石墨粉於電解液中對加工影響.................................................66
4-4-2流量對加工深度影響.................................................................67
4-4-3電解液流量對表面粗度影響.....................................................68
4-4-4進給速度對表面粗度影響.........................................................70
4-4-5石墨粉濃度對表面粗糙度影響.................................................73
4-5 結論.......................................................................................................76
第五章應用碳化矽粉加入電解液提升電化學放電加工性能之研究….…..77
5-1 前言.......................................................................................................77
5-2 實驗方法與原理...................................................................................80
5-3 實驗流程...............................................................................................85
5-4 結果與討論.........................................................................................87
5-4-1電解液流量對表面粗糙度影響...................................................87
5-4-2輸入電壓對表面粗糙度影響.......................................................88
5-4-3進給速度對表面粗糙度影響.......................................................90
5-4-4碳化矽含量對表面粗糙度影響...................................................92
5-4-5碳化矽粉於電解液中之加工機制與加工效能...........................94
5-5 結論...................................................................................................100
第六章總結論.................................................................................................101
參考文獻...........................................................................................................103
作者簡介...........................................................................................................109

圖目錄
圖2-1 ECDM之I-V特性曲線圖..................................................................14
圖2-2 先前學者實驗裝置示意圖…...............................................................17
圖2-3 本實驗裝置示意圖...............................................................................17
圖3-1 WECDM加工石英玻璃實驗設備示意圖................................................23
圖3-2 WECDM加工石英玻璃實驗流程圖........................................................28
圖3-3 電解液包覆石英玻璃及銅線電極之液滴形成至滴落整體變化.......30
圖3-4 線電極在液滴內從形成至滴落之接觸長度示意圖………………...32
圖3-5 液滴滴落時間與線電極接觸長度之關係……………………..……33
圖3-6 液滴內氧氣泡與氫氣泡分佈CCD相片及示意圖……………........34
圖3-7 液滴內流體流動方向CCD相片及示意圖………………................36
圖3-8 電壓對加工的影響..............................................................................37
圖3-9 電壓對電流之波型響應圖..................................................................39
圖3-10 電壓對加工深度影響之SEM圖............................................................39
圖3-11 電解液流量對加工深度及平均寬度影響...........................................41
圖3-12 電解液流量對加工深度影響之SEM圖................................................41
圖3-13 進給速度對加工深度及平均寬度影響...............................................43
圖3-14 進給速度與擴槽量示意圖...................................................................44
圖3-15 進給速度對加工深度影響之SEM圖...................................................44
圖3-16 液滴固定加工方式、連續流體加工方式、液滴滴定加工方式示意
圖與SEM圖及電流響應圖...............................................................49
圖3-17電解液流動方式對擴槽量及深度影響... .............................................50
圖3-18 WECDM液滴滴定法與雷射切割加工石英玻璃之SEM圖.......................51
圖3-19 WECDM液滴滴定法切割加工石英玻璃之SEM圖................................51
圖3-20 WECDM液滴滴定法切割加工不同形狀之石英玻璃SEM圖…………52
圖4-1 石墨粉加入電解液之加工實驗設備示意圖......................................59
圖4-2 WECDM液滴滴定法加工石英玻璃液滴滴落之CCD圖..........................62
圖4-3 WECDM液滴滴定法於未加入任何粉末之石英切割面SEM圖與液滴
內加入石墨粉之示意圖.......................................................................62
圖4-4 石墨粉於電解液內連續放電示意圖...................................................63
圖4-5 石墨粉加入電解液內加工石英玻璃之實驗流程圖...........................65
圖4-6 石墨粉於電解液中加工機制示意圖...................................................66
圖4-7 流量與加工深度關係...........................................................................67
圖4-8 電解液流量與表面粗糙度關係……………………...........................69
圖4-9 電解液流量與表面粗糙度關係之SEM圖..........................................69
圖4-10 進給速度與表面粗糙度關係...............................................................71
圖4-11 進給速度與表面粗糙度關係之SEM圖….........................................72
圖4-12 石墨粉末濃度與表面粗糙度關係.......................................................74
圖4-13 石墨粉末濃度與表面粗糙度關係之SEM圖.......................................75
圖5-1 碳化矽粉加入KOH電解液加工實驗設備示意圖...............................81
圖5-2 （a）電解液中加入碳化矽粉均勻分布於液滴內示意圖（b）碳化
矽粉為非導電物質，放電火花發生在銅電極與電解液之間示意圖.82
圖5-3 加入碳化矽粉之電解液流體在液滴內流動方向及加工機制示意圖
與放電火花分布區域CCD圖...............................................................83
圖5-4 碳化矽粉加入電解液內加工石英玻璃之實驗流程圖.......................86
圖5-5 電解液流量對表面粗糙度影響...........................................................87
圖5-6 輸入電壓對表面粗糙度影響...............................................................88
圖5-7 32V與35V電流密度分布圖...............................................................89
圖5-8 進給速度與表面粗糙度關係...............................................................90
圖5-9 進給速度對表面粗度影響之SEM圖...................................................91
圖5-10 碳化矽含量對表面粗糙度影響........................................................92
圖5-11 碳化矽含量對表面粗糙度影響之SEM圖........................................93
圖5-12 碳化矽粉加工機制示意圖與SEM圖................................................95
圖5-13 WECDM加工石英玻璃，未加入粉末與加入碳化矽粉於滴定電解
液中之SEM圖與電流密度分布響應圖............................................98
圖5-14 WECDM加工石英玻璃，加入碳化矽粉（5wt％）之微溝槽SEM
圖........................................................................................................99

表目錄
表 3-1石英玻璃化學性質及物理性質..............................................................24
表 3-2 黃銅線線電極的機械性質與物理性質................................................24
表 3-3 石墨的物理特性....................................................................................24
表 3-4 WECDM加工石英玻璃參數.....................................................................27
表 4-1 添加石墨粉加工石英玻璃實驗加工參數............................................63
表 5-1 添加碳化矽粉加工石英玻璃實驗加工參數........................................84
表 5-2 未加入粉末與加入碳化矽粉於電解液中之加工效能........................96

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指導教授

顏炳華(Biing-Hwa Yan)

審核日期

2015-6-25

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