膽管支架是一種特定幾何的簍空型支架，主要用於治療膽管堵塞，其方法為使用膽道內視鏡經由口腔進入，到達十二指腸乳突開口處，透過內視鏡的器械將支架置入膽管內。常見的材料為具有良好的機械性與生物相容性的鎳鈦合金與316L不鏽鋼。
此篇論文研究目的為膽管支架雷射切割後製程的改善與探討，主要分為探討噴砂加工及氣體擾動拋光最佳化兩部分。本研究先對支架噴砂加工進行探討，以氧化鋁磨粒搭配不同噴砂壓力，探討不同重量移除百分比對加工後支架品質的影響。研究過程以掃描式電子顯微鏡、綠光干涉儀及雷射共軛焦顯微鏡對其熔渣移除狀況、表面粗糙度及邊緣圓角化進行探討。由實驗結果得到在噴砂壓力60psig及重量移除百分比5%時，有最好的熔渣移除狀況與圓角化。
其次是關於不鏽鋼膽管支架在電解拋光製程中整體線寬移除不均勻的問題作為改善目標，本實驗使用田口實驗設計探討氣體擾動的三項參數:圓孔與支架的距離、圓孔數量與出氣壓力，並用方差分析與F-分布表判斷出顯著因子。在氣體擾動電解拋光中得到當圓孔與支架的距離5.5cm、圓孔數16、氣體壓力18kPa時有最佳的拋光後支架結構寬度均勻度。在方差分析中得到壓力為最顯著因子。

Biliary stent is a basket-shaped stent with a specific geometry. It is mainly used to treat biliary obstruction. The method is to use the biliary endoscopy to enter the mouth through the oral cavity, reach the opening of the duodenal mastoid, and place the stent into the bile duct through the instrument of the endoscope. Common materials are nickel-titanium alloy and 316L stainless steel due to their good mechanical and biocompatibility.
The purpose of this study is to improve and discuss the post process of laser cutting of biliary stents. It is mainly divided into two parts: sandblasting and gas disturbance polishing optimization. This study first discusses the sandblasting process of the stent, using alumina abrasive grains with different blasting pressures, to explore the effect of different weight removal on the quality of the stent after processing. In the research process, the slag removal status, surface roughness and edge rounding were discussed with scanning electron microscope, green light interferometry and laser confocal microscope. From the experimental results, the best slag removal condition and rounding are obtained when the blasting pressure is 60 psig and the weight removal amount is 5%. The second is dealing with the problem of uneven removal of the overall line width of the stainless steel biliary stent in the electropolishing process. This experiment uses the Taguchi experimental design to explore three parameters of gas disturbance: the distance between the circular hole and the stent, the number of circular holes and the outgassing stress, and uses analysis of variance and F-distribution table to determine the significant factor. In the gas-disturbed electropolishing, when the three parameters are the distance between the round hole and the stent is 5.5 cm, the round hole number is 16, and the gas pressure is 18kPa, there is the best uniformity of the width of the stent structure after polishing. The results indicate the pressure is the most significant factor in the analysis of variance.

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