Vascular stents - materials and manufacturing technologies

The objective of this article is to present materials and technology for the manufacture of vascular stents with appropriate design requirements. The use of the right material is very important in implantology. A biomaterial introduced into the circulatory system must be biocompatible and hemocompatible. At the same time, it should not initiate toxic, mutagenic, or immunological reactions. Currently, 316L stainless steel (316L SS), nitinol (Ni-Ti alloy) and cobalt-chromium alloy (Co-Cr) are used as standard stent materials. Additionally, drug-containing coatings are used to provide antithrombotic properties. Nowadays, scientists are trying to create biodegradable stents (BDS) using magnesium (Mg) or zinc (Zn) alloys. Laser methods are generally used to manufacture stents using Nd:YAG lasers with a pulse length in the range of several milliseconds. Material removal is based on the ejection of the melt using a high-pressure gas. The result is remelting and heat-affected zones. Various post-processing procedures are necessary to remove residues, including etching and electropolishing. Minimizing the heat-affected zone could be achieved by using femtosecond lasers. Additionally, immersion of the material in water prevents the deposition of residues on the workpiece. Interesting alternatives used in the manufacture of vascular stents are electrospinning or additive techniques. 3D printing enables obtaining of geometrically complex and personalized implants and reduces the consumption of materials and the production of waste.

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Opracowanie rekordu ze środków MEiN, umowa nr SONP/SP/546092/2022 w ramach programu „Społeczna odpowiedzialność nauki” - moduł: Popularyzacja nauki i promocja sportu (2022-2023)