電化學結合電泳精密拋光不銹鋼之研究

A study on stainless steel machining by using Electro-chemical machining with precise electrophoretic deposition polishing.

崔海平(Hai-Ping TSUI)

指導教授 ： 顏炳華

國立中央大學/工學院/機械工程學系/博士(2008年)

摘要

機械加工後之表面粗糙度改善，常需借助拋光製程來完成，但具微細尺寸磨粒之拋光磨輪由於製造上之困難性，磨粒粒徑1~2 μm以下之拋光磨輪較難製造。當具較大尺寸磨粒之拋光磨輪被應用於拋光製程時，所產生之拋光痕較寬，致使吾人無法獲得鏡面加工之效果，另微小孔洞經機械加工後，微小孔洞內壁之鏡面拋光，因孔徑微小，目前尚未有低成本及簡易之拋光方法。因此，如何鏡面拋光機械加工後表面及提升加工品質，是本論文所要探討的主題。
本研究針對不銹鋼材料表面粗糙度改善及提升加工品質，提出了三種改善方法，分別為電泳沉積鏡面拋光、精微螺旋電極電化學鑽孔加工及電化學結合電泳微孔複合加工。經由實驗結果分析顯示，電泳沉積法進行表面拋光，使用SiC粒徑顆粒大小為0.9~1.5 μm，可將Ra 0.5 μm的車削面及Ra 1.67 μm的放電面分別改善至Ra 0.03 μm及Ra 0.05 μm的鏡面;另一種方法為採用精微螺旋電極進行電化學鑽孔加工，電化學加工反應生成物能有效排出至加工區域外，可將圓柱電極加工後之入口孔徑425 μm與出口孔徑362 μm分別降為335 μm及299 μm，有效改善電化學鑽孔加工後的微孔形狀精度；第三種方法為電化學結合電泳微孔複合加工，係於精微螺旋電極表面電泳沉積SiC磨粒而製成微複合工具，並使用該微複合工具同時施行微電化學鑽孔加工及微孔洞研磨之複合加工，可將精微螺旋電極電化學鑽孔加工之Ra 0.4 µm降至Ra 0.041 µm，對改善表面粗糙度效果相當明顯。

關鍵字

拋光磨輪 ； 鏡面拋光 ； 電泳沉積 ； 電化學鑽孔 ； 微複合工具 ； 不銹鋼

並列摘要

Surface roughness of the machined parts can be improved by polishing process. Nevertheless, manufacturing polishing wheels with micro abrasive grains, especially those smaller than 1~2 μm, is extremely difficult. When polishing wheels with larger abrasive grains are used in polishing, the polishing marks on the surface of the specimen are wider. The mirror-like surface can not easily obtained. It is more difficult to polish the machined micro holes. In view of such drawbacks, this study aims to enhance the surface quality and precision of machined parts.
In this study, three approaches improve the surface roughness and machining precision of stainless steel plate are proposed. Three approaches are the mirror surface polishing by using the electrophoretic deposition method, Electro-chemical micro drilling (ECMD) by using helical tool, ECMD and Electrophoretic Deposition (EPD) polishing complex micro-hole machining. For the first approach, the experimental results indicate not only that SiC particles of size 0.9~1.5 µm were used in EPD polishing, but also that the initial roughness of the turning and the EDM machined surface could be improved from 0.5 µm Ra and 1.67 µm Ra to 0.03 µm Ra and 0.05μm Ra respectively. The second approach using a micro helical tool as a novel solution in ECMD process to improve the machining accuracy. The reaction products can be squeezed out of the machining zone. The inlet and outlet diameters of the micro holes could be improved from 425 μm and 362 μm using micro cylindrical tool to 355 μm and 299 μm respectively. Finally, ECMD and EPD polishing complex micro-hole machining experiment was performed. The micro helical tool can be deposited with SiC particles in Phenolic Formaldehyde Resin solution as a hybrid micro-tool by electrophoretic deposition phenomenon. The hybrid micro-tool is used in ECMD and EPD polishing complex micro-hole machining.experiments. When the helical tool is used, the inner surface roughness of micro hole is 0.4 µm Ra. When the hybrid micro-tool is used, the inner surface roughness of micro hole declines markedly to 0.041 µm Ra. The inner surface roughness of micro hole can be significantly improved.

並列關鍵字

stainless steel ； electrophoretic deposition ； hybrid micro-tool ； mirror surface polishing ； polishing wheel ； electrochemical drilling

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