Modeling and finite element simulation of sustainable coronary stent with a variation in unit cell design

This study presents a comprehensive finite element modeling and simulation approach to investigate the mechanical behavior of sustainable coronary stents with variations in unit cell design. The novelty of this research lies in the exploration of the mechanical performance of coronary stents made of titanium alloy (Ti-6Al-4 V) with different unit cell architectures, including hexagon, diamond, and auxetic structures. Titanium alloy (Ti-6Al-4 V) material is selected for stent construction owing to its wide range of sustainability such as biocompatibility, durability, longevity, reduced environmental Impact, and compatibility with advanced manufacturing processes. The performance of the modeled stent structures is analyzed via balloon compression and balloon expansion tests at 0.1, 0.3, and 0.5 mm displacement loading. The findings from the balloon compression test at 0.1 mm displacement concluded that the stiffest nature of auxetic stent structure showed the highest equivalent von Mises stress i.e. 1394 MPa, which is decreased by 13, and 16% for diamond, and hexagons respectively. The results from balloon expansion showed a similar trend at higher displacement as well, which confirmed the compliant nature of the hexagon stent structure. The results are in line with the relative density calculation of the unit cell.