生醫支架是一種中空管狀結構的醫療器材，主要被用於治療心血管疾病。種類主要有自我擴張式和氣球擴張型兩種，常見材料為鎳鈦合金和316L不鏽鋼。此二材料並皆具有良好的生物相容性。
此篇論文研究是將以光纖雷射所加工後的支架，探討其後處理製程並進行優化改良。主要針對研磨及電解拋光兩部分。首先是為改善不鏽鋼血管支架噴砂問題而新開發的漿體噴射研磨製程中其流場不穩定問題作為改善目標。此將透過泵浦取代氣體噴射作為動力源，以達到研磨漿體輸出穩定化，並以原製程參數為基礎再深入研究粒徑尺寸對表面形貌變化及邊緣圓角化的影響性；其次是關於鎳鈦合金膽管支架在電解拋光製程中支架拋光後線寬不均勻的問題作為改善目標。實驗中發現該問題為磁石旋轉擾動所造成，有鑑於此自行設計一氣體擾動系統用於電解拋光中改變電解液流動方式以改善拋光的不均勻性。並探討底部出氣位置、氣壓、電壓、移除量之最佳參數。由實驗結果得到使用中粒徑(平均82.5m)進行研磨的表面品質最佳並具有良好圓角化效果。在電解拋光中氣體擾動方式能減少支架拋光後的不均勻性，並在電壓25V、移除率40%和氣壓16kPa為最佳參數。

Biomedical stent is a medical device which is a metal tube and can be inserted into a vascular to relieve narrowing problem. Two types of stent can be distinguished, including balloon-dilatation type and self-expandable type. The most common materials are nickel-titanium alloy, called Nitinol, and 316L stainless steel. Both are high biocompatible.
The goal of this paper is to optimize the post laser machining treatment for biomedical stents. The experiment is divided into two main parts, slurry jet grinding (SJG) and electropolishing. Because of unsteadiness in previous slurry jet grinding study, the first part is changing the slurry driving-source from gas flow into a liquid pump to improve stability of fluid. The new slurry jet grinding experiment is based on previous process parameters and further to investigate the influences of grain size. In the past, the structure of the NiTi stent is uneven after electropolishing if the length of stent is long. Uneven structure may be due to the rotating magnetic stirrer in electropolishing tank. For the reason in the second part a self-designed gas stirred system is used in electropolishing tank and test if it can make whole stent uniformly. Several electropolishing parameters were investigated in this work to optimize the electropolishing process, including applied position of gas released, gas inlet pressure, voltage and total removed weight percentage. The results indicate slurry flow machining with middle grain size (82.5m) has better surface roughness and edge rounding effect. In the electropolishing study applied voltage 25V, 40% total removed weight percentage and pressure 16kPa can achieve good finished stent shape and surface quality.

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