CAJ | 학술논문

利用非线性有限元方法仿真模拟不锈钢(SUS-316 L)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807.9 MPa,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。
이용비선성유한원방법방진모의불수강(SUS-316 L)3충불동결구관맥지가동정태우합확장과정화생물역학성능。연구지가재압악수축、자유확장、사재과정이급맥류순배변응력지속작용과정중유한원모형적망격화분、재료본구모형건립、변계조건、재하정의화접촉처리등관건기술。근거유한원계산결과득도료3충지가재우합확장과정중최대등효응력위807.9 MPa,최대소성응변위0.208；3충지가적축향축단솔、경향반탄솔、확장불균균성도재13%이내,정태안전계수>1.3,동태안전계수>1.1；병여실험측시수거진행분석비교,이론분석여체외확장실험결과문합교호,오차재7%이내,험증료유한원모의적준학성화합이성。본문적모의방법위관맥지가적우화설계、신산품개발이급림상평고제공료과학적의거。
The dynamic-static coupling expansion process and biomechanical properties for three kinds of stain-less steel (SUS-316L)coronary stents were investigated using nonlinear finite element method.The key tech-nologies such as meshing,material constitutive model,boundary conditions,loading definition and contact in-teraction,were discussed in detail,as the stent underwent the crimp induced-contraction,free expansion,un-loading and continuous pulsation circulating stresses.According to finite element analysis (FEA)results,dur-ing the coupling expansion of stents,the maximum equivalent stress was 807.9 MPa,and the maximum plastic strain was 0.208;the axial shortening rate,radial bounce rate and expanding nonuniformity of three stents were all within 1 3%,while the static safety factor was over 1 .3 ,and the dynamic safety factor was over 1 .1 .The numerical results agreed well with experimental data and the error was less than 7%,strongly demonstrating the rationality and validity of FEA results.The proposed simulation method provides a scientific basis for the optimization and clinical evaluation of the coronary stents.