臺灣博碩士論文加值系統

微放電加工(μ-EDM)是以微小能量直接投入加工區域，進行非接觸方式加工，加工過程穩定、精度高、材料移除率小，可加工出真實三維複雜形狀與難以加工材質之精微模具與零件。一般傳統μ-EDM常配合線放電研磨(Wire Electrical Discharge Grinding，WEDG)機構修整微電極，由於標準WEDG機構只能做水平加工，且加工速度慢，所以本研究首先設計一超音波振動輔助線放電研削機構(Ultrasonic Assisted WEDG)與附增旋轉軸，再運用此機構修整出不同傾斜角度的曲面與螺紋微電極(以製備刀具及微細零件)，配合超音波振動輔助下，改善其加工精度、表面品質、材料移除率，以提升加工效率與更精緻多元化微電極為主要目標。其次將修整好之螺旋微電極(刀具)實際應用於微放電鑽孔與微放電銑削初步測試，研究其放電加工的效率，以及電極的消耗與補償。使用自製超音波振動輔助線放電研磨機構，目前比傳統WEDG可迅速修整出50μm以下直徑特殊曲面的微電極，WEDG機構加工時間約30分鐘，UA-WEDG機構加工時間約23分鐘，節省時間至少20%，再配合CNC加工路徑程式對工件(例如SUS 304)進行放電鑽孔與放電銑削。針對放電加工會有微電極(刀具)消耗的問題，需考慮微電極的補償量，本研究使用統計廻歸分析方式找出電極消耗量與實際加工深度，由此計算出補償量再進行補償實驗。實驗結果螺紋電極放電鑽孔擴孔量比圓柱電極少，放電鑽孔加工時間，螺紋電極比圓柱電極至少快35%，綜言之，本文提出新式WEDG線放電研磨機構與高效率放電鑽孔與放電銑削製程與刀具。尤其比較螺紋電極於鑽孔與銑削時，與一般柱狀電極的消耗及排屑差異性，以提升加工效率與品質為目標，並擴增微放電加工能力，完成設計製備微刀具及微放電加工之實驗。

Micro EDM provides a non-contact machining process with energy throughput directly into the working zone. Its machining energy can be stably controlled under a precise small level, therefore, its removal rate is small and its precision capability can produce real three dimensional micro parts and precision mold/die features. Conventional micro EDM processes rely on time-consuming Wire Electrical Discharge Grinding (WEDG) to achieve acceptable quality of micro tools and only 2-D contours can be conducted by the horizontal configuration. In this study, a rotational axis augmented to standard WEDG processes with ultrasonic assistance and its applications to efficient dressing are reported. Different inclined angles can be arranged from -15 degree to +15 degree. First of all, an ultrasonic assisted WEDG system (UA-WEDG) is developed for high-speed preparing helix or special profile of micro-electrodes to serve as tools. Significant effects on dressing efficiency by the novel UA-WEDG system were verified experimentally. It was found at least 23% of time saving can be obtained for WC tool electrodes from raw material of 500μm to 50μm in diameter.
Then, micro EDM drilling and milling are conducted with the prepared micro-tools. The machining efficiency and the surface quality of the micro EDM workpiece are major concerns. For micro-drilling with 0.3 mm of SUS 304 thin platelet, the proposed helical tools can reduce the machining time up to 35% over conventional cylinder tools of 100μm diameter. Its expansion of inner holes diameter is also significantly reduced in compared with cylinder tools. Because of its geometric properties, the helical surface contributed to expelling debris from the machining region, especially, in deep-hole drilling or long aspect-ratio machining. But, after considering the wear compensation of micro-tools through series of wear experiments and statistical regression, the novel tools reveals less significant time saving and almost negligible accuracy improvement for a single step EDM milling of a 0.5 x 0.5 area with 0.05 mm depth. Therefore, a novel WEDG mechanism with ultrasonic assisted rotational axis is established and a better configuration with new micro-tools is also introduced into the micro EDM fields.

摘要…………………………………………………………………………………………………………ii
ABSTRACT…………………………………………………………………………………………………………………………………………………………iii
誌謝…………………………………………………………………………………………………………v
目錄…………………………………………………………………………………………………………vi
表目錄……………………………………………………………………………………………………viii
圖目錄………………………………………………………………………………………………………ix
符號說明……………………………………………………………………………………………………xv
第一章 ： 緒論……………………………………………………………………………………………1
1-1-1 研究動機………………………………………………………………………………………1
1-2-1 研究目的………………………………………………………………………………………3
1-3-1 本文架構………………………………………………………………………………………3
1-4-1 文獻回顧………………………………………………………………………………………4
1-4-1 微放電修整微電極成形技術…………………………………………………………………4
1-4-2 超音波輔助加工………………………………………………………………………………8
1-4-3 放電銑削與補償技術…………………………………………………………………………10
第二章 ： 基本原理………………………………………………………………………………………14
2-1-1 放電加工基本原理……………………………………………………………………………14
2-1-1 放電加工原理…………………………………………………………………………………14
2-1-2 放電加工材料移除機制………………………………………………………………………15
2-1-3 放電迴路的種類與波形圖……………………………………………………………………18
2-1-4 微放電加工介紹………………………………………………………………………………21
2-1-5 微放電加工參數與影響性……………………………………………………………………21
2-1-6 線放電研削加工法……………………………………………………………………………23
2-2-6 超音波加工基本原理…………………………………………………………………………23
2-2-1 超音波加工原理………………………………………………………………………………23
2-2-2 超音波輔助加工………………………………………………………………………………24
第三章 ： 實驗設備與方法………………………………………………………………………………25
3-1-2 實驗設備………………………………………………………………………………………25
3-2-2 實驗材料………………………………………………………………………………………37
3-3-2 實驗方法………………………………………………………………………………………37
3-4-2 實驗參數設定…………………………………………………………………………………37
3-5-2 實驗流程………………………………………………………………………………………38
第四章 ： 機構設計與參數規劃…………………………………………………………………………40
4-1-2 UA-WEDG機構一代設計……………………………………………………………………40
4-2-2 UA-WEDG機構二代設計……………………………………………………………………41
4-3-2 UA-WEDG機構二代設計完成………………………………………………………………42
4-4-2 UA-WEDG機構穩定性檢測…………………………………………………………………45
4-5-2 實驗規劃………………………………………………………………………………………47
第五章 ： 實驗結果與討論………………………………………………………………………………48
5-1-1 超音波實驗分析與加工補償…………………………………………………………………48
5-1-1 小超音波頭前端連接之振動頭針設計分析…………………………………………………48
5-1-2 小能量與大能量修整電極比較………………………………………………………………54
5-1-3 傳統WEDG機構與自製UA-WEDG機構加工速度比較………………………………………54
5-1-4 普通圓柱電極放電鑽孔與放電銑削…………………………………………………………57
5-1-5 圓柱電極放電鑽孔之消耗與補償量計算……………………………………………………58
5-1-6 圓柱電極放電銑削之消耗與補償量計算……………………………………………………60
5-1-7 圓柱電極運用於放電銑削(粗加工)……………………………………………………………………………………………64
5-2-1 螺紋電極實驗結果……………………………………………………………………………67
5-2-1 超音波輔助UA-WEDG機構修整螺紋電極…………………………………………………67
5-2-2 標準WEDG機構修整螺紋電極………………………………………………………………69
5-2-3 UA-WEDG修整圓柱電極與螺紋電極放電鑽孔加工比較…………………………………71
5-2-4 不同螺紋數電極放電鑽孔加工速率比較……………………………………………………98
5-2-5 不同轉速配合同螺紋數之電極放電鑽孔加工比較………………………………………101
5-2-6 螺紋電極放電鑽孔與放電銑削……………………………………………………………103
5-2-7 螺紋電極放電鑽孔之消耗與補償量計算…………………………………………………104
5-2-8 螺紋電極放電銑削之路徑消耗與補償量計算……………………………………………106
5-2-9 圓柱與螺紋電極放電鑽孔之消耗與補償量比較…………………………………………110
5-2-10 圓柱與螺紋電極放電銑削之路徑消耗與補償量比較……………………………………111
5-2-11 螺紋電極運用於放電銑削(粗加工)…………………………………………………………………………………………112
5-3-1 螺紋電極角度控制…………………………………………………………………………117
第六章 ： 結論…………………………………………………………………………………………121
第七章 ： 未來展望……………………………………………………………………………………124
參考文獻…………………………………………………………………………………………………126
簡歷………………………………………………………………………………………………………129

[1]Z. N Guo, T. C. Lee, T. M. Yue, W. S. Lau (1997), "Study on the machining mechanism of WEDM with ultrasonic vibration of the wire", Journal of Materials Processing Technology 69: 212-221。
[2]Z. Y. Yu, T. Masuzawa, M. Fujino (1997), "Micro-EDM for Three-Dimensional Cavities - Development of Uniform Wear Method", CIRP Annals - Manufacturing Technology 47(1): 169-172。
[3]K. P. Rajurkar, Z. Y. Yu (2000), "3D Micro-EDM Using CAD/CAM", CIRP Annals - Manufacturing Technology 49(1): 127-130。
[4]P. Bleys, J. P. Kruth, B. Lauwers, A. Zryd, R. Delpretti, C. Tricarico (2002), "Real-time Tool Wear Compensation in Milling EDM", CIRP Annals - Manufacturing Technology 51(1): 157-160。
[5]P. Bleys, J. P. Kruth, B. Lauwers (2004), "Sensing and compensation of tool wear in milling EDM", Journal of Materials Processing Technology 149(1-3): 139-146。
[6]J. Fleischer, T. Masuzawa, J. Schmidt, M. knoll (2004), "New applications for micro-EDM", Journal of Materials Processing Technology 149(1-3): 246-249。
[7]Yao-Yang Tsai, Takahisa Masuzawa (2004), "An index to evaluate the wear resistance of the electrode in micro-EDM", Journal of Materials Processing Technology 149(1-3): 304-309。
[8]Q. H. Zhang, R. Du, J. H. Zhang, Q. B. Zhang (2006), "An investigation of ultrasonic-assisted electrical discharge machining in gas", International Journal of Machine Tools and Manufacture 46(12-13): 1582-1588。
[9]Naotake Mohri, Takayuki Tani (2006), "Micro-pin Electrodes Formation by Micro-Scanning EDM Process", CIRP Annals - Manufacturing Technology 55(1): 175-178。
[10]Dong-Jun Kim, Sang-Min Yi, Young-Soo Lee, Chong-Nam Chu (2006), "Straight hole micro EDM with a cylindrical tool using a variable capacitance method accompanied by ultrasonic vibration", Journal of Micromechanics and Microengineering 16: 1092-1097。
[11]B. Lauwers, J. P. Kruth, K. Brans (2007), "Development of Technology and Strategies for the Machining of Ceramic Components by Sinking and Milling EDM", CIRP Annals - Manufacturing Technology 56(1): 225-228。
[12]Mu-Tian Yan, Kuo-Yi Huang, Chin-Yen Lo (2008), "A study on electrode wear sensing and compensation in Micro-EDM using machine vision system", The International Journal of Advanced Manufacturing Technology 42(11-12): 1065-1073。
[13]Gwo-Lianq Chern, Jyun-Cheng Cheng (2008), "Development of a micro-EDM/milling machine and study on micro-machining using micro-tools", Journal of the Chinese Society of Mechanical Engineers Vol.29, No.1: 53-60。
[14]Takashi Endo, Takayuki Tsujimoto, Kimiyuki Mitsui (2008), "Study of vibration-assisted micro-EDM—The effect of vibration on machining time and stability of discharge", Precision Engineering 32: 269-277。
[15]M. G. Xu, J. H. Zhang, Y. Li, Q.H. Zhang, S.F. Ren (2009), "Material removal mechanisms of cemented carbides machined by ultrasonic vibration assisted EDM in gas medium", Journal of Materials Processing Technology 209(4): 1742-1746。
[16]Yuan-Gang Wang, Fuling Zhao, Jin Wang (2009), "Wear-resist Electrodes for Micro-EDM", Chinese Journal of Aeronautics 22: 339-342。
[17]Mao-Sheng Li, Guan-Xin Chi, Zhen-Long Wang, Yu-Kui Wang, Li Dai (2009), "Micro electrical discharge machining of small hole in TC4 alloy", Transactions of Nonferrous Metals of China 19: 434-439。
[18]Mu-Tian Yan, Shr-Shiang Lin (2010), "Process planning and electrode wear compensation for 3D micro-EDM", The International Journal of Advanced Manufacturing Technology 53(1-4): 209-219。
[19]Hui-Lan Yu, Ji-Jie Luan, Jian-Zhong Li, Yu-Sheng Zhang, Zu-Yuan Yu, Dong-Ming Guo (2010), "A new electrode wear compensation method for improving performance in 3D micro EDM milling", Journal of Micromechanics and Microengineering 20(5): 055011。
[20]E. Aligiri, S. H. Yeo, P. C. Tan (2010), "A new tool wear compensation method based on real-time estimation of material removal volume in micro-EDM", Journal of Materials Processing Technology 210: 2292-2303。
[21]黃豐元、顏炳華、陳建良 (2003), "結合微細放電與高頻振動研磨之微孔加工研究", 國立中央大學機械工程研究所碩士論文。
[22]黃永河、周昭宇、林清田、陳源豐、林炎成、卓漢明 (2003), "線切割電極附加超音波振動對碳化鎢加工特性影響之研究", 第二十屆機械工程研討會: 1081-1088。
[23]廖運炫、陳順同、林常盛 (2005), "多工型高精密微小加工機之研發與微元件製造", 機械月刊, 第三十一卷(第三期): 64-79。
[24]顏炳華、洪榮洲 (2007), "微放電複合製程之微型工具製作技術及其精微加工研究", 國立中央大學機械工程研究所博士論文。
[25]黃國益、楊淳良、徐嘉偉 (2008), "nsc 微放電加工之微電極尺寸磨耗率及深度之即時監控", 行政院國家科學委員會研究計畫報告。
[26]楊忠義 (2008), "超音波輔助機械加工", 機械月刊, 第三十四卷(第三期): 40-48。
[27]許坤明 (2010), "非傳統加工", 第二章, 第三版, 全華書局, 台灣。
[28]陳順同 (2011), "模具精密加工 <精密模具成型技術(Laser, Cutting, EDM, w-EDM)>", 台灣區模具工業同業公會, 模具精密加工-上課講義。
[29]許富銓 (2011), "精微放電加工發展現況<微放電加工(μ-EDM)與微線切割加工(μ-WEDM)>", 金屬工業研究發展中心(MIRDC), 精微成形研發處, 模具與精微加工組, 高應大校內演講。
[30]楊忠義 (2011), "超音波輔助製造技術與設備發展", 金屬工業研究發展中心(MIRDC), 精微成形研發處, 模具與精微加工組, 高應大校內演講。