Research On Support Performance For Magnesium Alloy Coronary Stents

Magnesium alloy stents as one of the biodegradable stent, have been the currentresearch hot spots and trends. However, compared with stainless steel stents,magnesium alloy stents have lower radical support stiffness and lower mechanicalproperties. In consideration of the premises, this study optimized and designed thestructure of the magnesium alloy stent in order to cover the shortage of materialproperty itself. A coronary stent is formed by the supports and connectors alternately.The support is a major component of the stent, and has a great influence on theexpansion, the support performance and mechanics performance.This research group self-developed WE43magnesium alloy stent has beenstudied by the finite element method(by the Abaqus software). By means of changingthethickness(T-series),strut width(H-series) and radius of curvature(R-series)structureparameters of coronary stent unit, this study evaluated the mechanical properties ofstents in static state. At the same time the rationality of numerical simulation wasverified, which presented measure methods of bracing stiffness for magnesium alloystents which was based on radical uniform load measure technology.In the study, the result shows: increasing the thickness of stents has no effect onthe most equivalent stress and strain and the safety factor, it can reduce the radialspring rateand raise the coefficient of axial and the nonuniformity in expansion, andthe same time it can improve its support performance. Increasing the strut width ofstents can increase the most equivalent stress and strain, it can reduce the radial springrate and the safety factor, increase the coefficient of axial and the nonuniformity inexpansion, and the same time it can improve its support performance. Increasing thestrut radius of curvature can reduce the most equivalent stress and strain, it also canreduce the coefficient of axial and the nonuniformity in expansion and increase theradial spring rate and the safety factor, and the same time it can improve its supportperformance. It is provided scientific guidance for the design and development of thebiodegradable stent by simulating and analyzing their static state and support performance of the magnesium alloy coronary stent.