電化學微加工（Electrochemical Micro-Machining，EMM），屬於非傳統加工方法的一種。其優點有不受材料硬度與強度的影響，可加工任何金屬材料，刀具無耗損，加工速度快且工件表面不含殘留應力，工件無熱變質層之生成及表面粗糙度佳等。並且具有設備低廉、大量製造以及降低成本等優勢，是目前公認最具有發展潛力的新興產業之一。
灰色關聯分析是以有限的實驗來獲得最多的實驗結果，並分析實驗參數對加工品質之影響程度且找到最佳參數組合的一種方法，其優點在於可以同時進行多重特性之評估。本研究使用自行設計之金屬遮罩，以紅銅作為刀具，厚度為0.1mm的不鏽鋼SUS301薄板作為工件，進行遮罩電化學穿孔實驗，以驗證金屬遮罩之可行性。以灰色關聯分析方法作為工具分析實驗結果，探討遮罩電化學加工參數（電解液濃度、操作電壓、遮罩孔洞直徑、遮罩厚度）對於底切、均勻度及真圓度之影響趨勢，並找到加工範圍內之最佳參數。
通過實驗結果可以發現，在使用雙面膠增加工件與遮罩間的貼合度後，金屬遮罩可以運用在遮罩電化學加工之中。對於加工成品之特性影響最大的實驗參數為遮罩孔洞直徑與遮罩厚度，而實驗之最佳參數組合(A_3 B_3 C_2 D_1)為:電解液濃度16wt%、操作電壓18V、遮罩孔洞直徑1.2 mm、遮罩厚度0.1mm。加工結果如下：底切為0.07mm、平均偏差量為0.04mm與圓度誤差為0.18mm。與初始條件相比，其灰色關聯度從0.53提升到0.98，其值將近於目標理想值。

關鍵字：遮罩式電化學加工，灰色關聯分析

Electrochemical machining (ECM) is one of the non-traditional manufacturing processes. The advantages of ECM include not being affected by the hardness and strength of the material,applicable to any metal material , fast processing speed and no surface residual stress, no heat zone and smooth workpiece surface. Furthermore , it has merits of lower price in equipments, mass production and lower costs, etc.Currently,it’s considered as one of the most promising industry.
Grey relational analysis (GRA) is a method of obtaining the most experimental results by limited experiments, and analyzing the influence of experimental parameters on the processing quality and finding the best combination of parameters, the advantage of GRA is that it could have multi-objective optimization. This study uses a self-designed metal mask, uses pure copper as a tool, stainless steel SUS301 sheet with a thickness of 0.1 mm as a workpiece, Perform TMEMM processing experiments to verify the feasibility of the metal mask. GRA is used to analyze the influences of parameters (e.g.: electrolyte concentration, applied voltage, diameter of the mask hole, and the thickness of the mask) on the undercut, uniformity and roundness of array holes, and estimate the best combination of parameters.
Through the experimental results, it can be found that the metal mask can be used in the electrochemical processing of the mask after the double-sided adhesive is used to increase the fit between the workpiece and the mask. The most important factors for the characteristics of finished products are diameter of the mask hole and thickness of the mask and the best parameter combination is A_3 B_3 C_2 D_1 (electrolyte concentration 16wt%, applied voltage 18V, diameter of the mask hole 1.2 mm, and the thickness of the mask 0.1mm). The processing results were as follows: the undercut was 0.07 mm, the average deviation was 0.04 mm, and the roundness error was 0.18 m. Compared with the original working condition (A1B1C1D1), the GRA is increased from 0.34 to 0.96. It is closed to the ideal working condition.

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