支架是一種用於治療冠心病患者的微小絲網管。支架性能受其支柱和連桿設計的影響。用於構建支架的材料也會影響其關於支架受壓力測試而膨脹的能力。本文針對球囊擴張支架在響應各種充氣壓力時的數值結果進行優化分析。 3D支架模型的尺寸為長20毫米，外徑1.6毫米。透過使用Abaqus 6.13軟件的有限元法（FEM）對各種充氣壓力進行測試，以獲得機械性能，如von mises，徑向反沖，縱向反沖，縮短和膨脹直徑。本論文使用各種充氣壓力對具有50μm，75μm和100μm的各種支架厚度的支架進行模擬。然後利用響應面法（RSM）利用支架厚度和充氣壓力參數優化模擬結果。結果顯示，最佳支架設計為PLLA材料，厚度為50μm，膨脹壓力為0.0273 MPa的支架。該最佳參數為64 MPa，徑向反沖為35.11％，縱向後坐為-3.52％，縮短為4.43％，膨脹直徑為2.46 mm。至於PDLLA而言，最佳結果是厚度為50μm且膨脹壓力為0.0141MPa的支架。該最佳參數為33 MPa，徑向反沖為19.54％，縱向後坐為-0.85％，縮短為1.11％，膨脹直徑為2.29 mm。根據結果，PLLA材料具有較好的機械強度和降解率。

The stent is a tiny wire mesh tube one for treating patients with coronary heart disease. The stent performance is affected by the design of its strut and link. The material used to build the scaffold also affects its performance regarding the ability of a stent to expand due to the pressure test. This paper presents the optimization of a numerical result of a balloon expandable stent in responding to various inflated pressures. A 3D stent model is made with a size of 20 mm long and an outer diameter of 1.6 mm. It is tested with various inflated pressure by using finite element method (FEM) with Abaqus 6.13 software in order to obtain the mechanical performance such as von mises, radial recoil, longitudinal recoil, foreshortening, and inflated diameter. Simulations are performed on stents with various stent thickness of 50 µm, 75 µm, and 100 µm by using various inflated pressures. The simulation results are then optimized by using response surface method (RSM) with the parameters of stent thickness and inflated pressure.
The results show that the optimal stent design is stent with a thickness of 50 µm and expansion pressure of 0.0273 MPa for PLLA. The responses generated from this optimal parameter are von mises of 64 MPa, radial recoil of 35.11%, longitudinal recoil of -3.52%, foreshortening of 4.43%, and an inflated diameter of 2.46 mm. While for PDLLA, the optimal result is a stent with a thickness of 50 µm and expansion pressure of 0.0141 MPa. The responses generated from this optimal parameter are von mises of 33 MPa, radial recoil of 19.54%, longitudinal recoil of -0.85%, foreshortening of 1.11%, and an inflated diameter of 2.29 mm. Based on the results, PLLA wins because it has better mechanical strength and degradation rate.

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