膽管支架放置術是一種侵入性較小的治療方法，而且成功率高、併發症低，是膽管阻塞疾病患者的理想治療方式，該手術是用細導管將支架送至膽管阻塞部位，支架擴張後撐開阻塞的膽管，使膽汁流通，使患者的病症得以緩解。
本研究以市售支架之結構尺寸，並利用三維實體建模軟體 Pro/Engineer 與有限元素分析軟體 ANSYS 建立不同結構設計之鎳鈦合金支架模型，對其徑向強度、柔順性、植入性能和應變分佈進行分析及改良，最後成功設計出一新型支架結構。本研究使用光纖雷射進行加工，以不銹鋼管及鎳鈦合金管材料進行測試，利用焦距、功率、脈衝重複頻率等參數進行測試並找出適合加工之條件，且利用控制器同步雷射觸發功能成功改善原先雷射加工產生的熱效及翹曲的問題，並以加工路徑偏移的方式降低製程所需的時間。此外，在熱處理實驗中，將探討形狀記憶合金在不同熱處理溫度、恆溫時間及冷卻方式下，記憶效應、相轉變溫度及機械性質上之改變趨勢。

Endoscopic biliary stenting is an invasive treatment method with high success rate and low complication. It is a treatment for bile duct obstruction disease patients. The surgery put thin catheter stent in the bile duct obstruction site, then the stent expand by itself, final the bile flowed by the blockage of the bile ducts, so that the patient's symptoms to be alleviated.
This study first builds up the model by Pro/Engineer based on the structure size of commercial stents. The strain distribution of nitinol stents and the desired pattern which is more flexibility and the higher radial force are discussed by the finite element analysis software ANSYS. In biliary stent fabrication, fiber laser is determined to cut nitinol and stainless tubes. This study focuses on optimizing the laser parameters such as focal position, average power, and pulse repetition rate. The results show that the heat affected zone and fabrication time can be reduced by programmable synchronized output and cut with path offset. Furthermore, heat treatment experiments were carried out on the trend of shape memory alloy material properties in different treatment temperature, treatment time and cooling methods.

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