Bukala Jakub, Buszman Piotr P, Małachowski Jerzy, Mazurkiewicz Lukasz, Sybilski Kamil
Institute of Mechanics and Computational Engineering, Faculty of Mechanical Engineering, Military University of Technology, Gen. Sylwestra Kaliskiego 2, 00-908 Warsaw, Poland.
Center for Cardiovascular Research and Development American Heart of Poland, Czajek 41, 40-534 Katowice, Poland.
Materials (Basel). 2020 Apr 24;13(8):2003. doi: 10.3390/ma13082003.
The use of bioresorbable polymers such as poly(lactic-co-glycolic acid) (PLGA) in coronary stents can hypothetically reduce the risk of complications (e.g., restenosis, thrombosis) after percutaneous coronary intervention. However, there is a need for a constitutive modeling strategy that combines the simplicity of implementation with strain rate dependency. Here, a constitutive modeling methodology for PLGA comprising numerical simulation using a finite element method is presented. First, the methodology and results of PLGA experimental tests are presented, with a focus on tension tests of tubular-type specimens with different strain rates. Subsequently, the constitutive modeling methodology is proposed and described. Material model constants are determined based on the results of the experimental tests. Finally, the developed methodology is validated by experimental and numerical comparisons of stent free compression tests with various compression speeds. The validation results show acceptable correlation in terms of both quality and quantity. The proposed and validated constitutive modeling approach for the bioresorbable polymer provides a useful tool for the design and evaluation of bioresorbable stents.
在冠状动脉支架中使用聚乳酸-乙醇酸共聚物（PLGA）等生物可吸收聚合物理论上可降低经皮冠状动脉介入治疗后并发症（如再狭窄、血栓形成）的风险。然而，需要一种将实施的简易性与应变率依赖性相结合的本构建模策略。在此，提出了一种用于PLGA的本构建模方法，该方法包括使用有限元法进行数值模拟。首先，介绍了PLGA实验测试的方法和结果，重点是不同应变率下管状试样的拉伸试验。随后，提出并描述了本构建模方法。基于实验测试结果确定材料模型常数。最后，通过对不同压缩速度下支架自由压缩试验的实验和数值比较，验证了所开发的方法。验证结果在质量和数量方面均显示出可接受的相关性。所提出并经验证的生物可吸收聚合物本构建模方法为生物可吸收支架的设计和评估提供了一个有用的工具。
