Effect of the ultrasonic melt treatment on the deployment outcomes of a magnesium stent manufactured by microcasting: a finite element analysis

To achieve better outcomes from the deployment of a stent in a stenosed artery may be dependent on several factors in which the applied material properties are included. The application of ultrasonic (US) treatment to magnesium alloy melt has proven to enhance its properties regarding tensile strength and elongation, which could be used to improve the performance of a stent. In this study, two stents built in as-cast and US-treated AZ91D are compared regarding their expansion ability, dogboning, foreshortening, and recoil results, using finite-element analysis. The US-treated stent achieves greater diameters at full expansion than the as-cast AZ91D one, whilst their dogboning and foreshortening results are comparable. The as-cast AZ91D stent presents the lowest values of radial elastic recoil, being the longitudinal recoil equal for both studied cases.