不锈钢冠脉支架耦合扩张变形生物力学性能的模拟研究

发布时间：2018-11-16 20:50

【摘要】：利用非线性有限元方法仿真模拟不锈钢(SUS-316L)3种不同结构冠脉支架动静态耦合扩张过程和生物力学性能。研究支架在压握收缩、自由扩张、卸载过程以及脉流循环变应力持续作用过程中有限元模型的网格划分、材料本构模型建立、边界条件、载荷定义和接触处理等关键技术。根据有限元计算结果得到了3种支架在耦合扩张过程中最大等效应力为807.9MPa,最大塑性应变为0.208;3种支架的轴向缩短率、径向反弹率、扩张不均匀性都在13%以内,静态安全系数1.3,动态安全系数1.1;并与实验测试数据进行分析比较,理论分析与体外扩张实验结果吻合较好,误差在7%以内,验证了有限元模拟的准确性和合理性。本文的模拟方法为冠脉支架的优化设计、新产品开发以及临床评估提供了科学的依据。
[Abstract]:Nonlinear finite element method was used to simulate the dynamic and static coupling expansion process and biomechanical properties of three kinds of stainless steel (SUS-316L) coronary stents. The key techniques such as mesh generation of finite element model, material constitutive model establishment, boundary condition, load definition and contact treatment are studied in the process of clamping shrinkage, free expansion, unloading process and continuous action of pulse-flow variable stress. According to the results of finite element calculation, the maximum equivalent stress and plastic strain are 807.9 MPA and 0.208 respectively. The axial shortening rate, radial rebound rate and expansion inhomogeneity of the three kinds of scaffolds are all within 13%, static safety factor 1.3, dynamic safety factor 1.1; Compared with the experimental data, the theoretical analysis is in good agreement with the results of in vitro expansion experiment, and the error is less than 7%, which verifies the accuracy and rationality of the finite element simulation. The simulation method provides a scientific basis for the optimal design of coronary stent, the development of new products and the clinical evaluation.
【作者单位】：内蒙古工业大学机械学院;
【基金】：国家自然科学基金资助项目(81160186) 内蒙古自然科学基金资助项目(2011BS0708) 内蒙古自治区高等学校科学研究资助项目(NJZY11077) 内蒙古工业大学科学研究资助项目(ZD201109)
【分类号】：R318.08

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