Innowacyjne bioabsorbowalne materiały na bazie cynku do potencjalnych zastosowań na stenty mózgowo-naczyniowe

Cerebrovascular diseases, such as transient ischemic attack (TIA), stroke, and aneurysm are on the rise among civilization diseases. In an aging society, the development of materials for biomedical devices becomes crucial. Cerebrovascular stents and devices serve specific functions in the body, supporting tissue regeneration and becoming no longer needed once their role is fulfilled. Therefore, there has been a great increase in interest in biodegradable materials, i.e. those that dissolve in physiological conditions and their products are not harmful to the living organism. The use of such an implant reduces side effects typical of permanent implants, such as inflammation or thrombosis. Novel biodegradable metallic materials include magnesium, iron, and zinc. Among them, pure zinc has an optimal corrosion rate in physiological fluids. The potential application of these materials depends on the specific requirements that must be met. A set of features such as degradation rate, mechanical properties, and biocompatibility can be improved using alloying or plastic deformation. Alloying additives (for zinc mainly Mg, Li, Ag but also Mn, Cu, Fe, and rare earth elements) and plastic deformation (hot extrusion, hydrostatic extrusion) can improve the strength of pure zinc. The development in this area needs to be focused on advanced alloy design and fabrication techniques. There is still a lack of comprehensive investigation of the properties of the materials that meet the requirements for particular applications. This required to analyze and determination of the mechanisms of plastic deformation and the impact of grain size, intermetallic phase distribution, and size on the corrosion properties and mechanical performance. Proper choice of alloying elements is essential. For investigation, the ZnMgMn ternary alloys were chosen. The main aim of the research is to explain the influence of alloying and plastic deformation on the mechanical and corrosion properties of the tested alloy in order to obtain a good combination of strength and ductility. The additional aim of the research is to obtain uniform corrosion properties and good biocompatibility by dispersing and refining intermetallic phases and surface modification through plasma treatment by plasma immersion ion implantation (PIII). The hypothesis is assumed that by optimization of the parameters of plastic deformation, alloying with magnesium and manganese, and surface treatment the proper combination of strength and ductility could be an asset, with stable mechanical properties, uniform corrosion, and good biocompatibility. The research will be conducted alongside two Polish partners the IMIM PAN (Institute of Metallurgy and Materials Science of the Polish Academy of Sciences) and the IWC PAN (Institute of High Pressure of the Polish Academy of Sciences) and in international cooperation with Université Laval (ULaval) in Canada. The main area of investigations carried out at the IMIM PAN will consist of advanced microstructural characterization with some parts of corrosion studies. The IWC PAN will deal with the method of plastic deformation (hydrostatic extrusion) and mechanical tests. At ULaval plasma treatment by plasma immersion ion implantation (PIII) will be performed and surface analysis in order to determine the corrosion properties and biocompatibility of the investigated alloys. All institutions based on the obtained results will try to explain the mechanisms which control microstructure formation in deformed alloys, having a great impact on mechanical and corrosion properties. The innovative approach proposed in the project covers the development of ternary alloys with an introduction of second-phase particles in a controlled way and improvement of the mechanical properties by alloying and hydrostatic extrusion together with a beneficial impact on corrosion and biological properties additionally supported by surface modifications with by plasma immersion ion implantation (PIII). Multicomponent zinc alloys can positively affect key aspects of bioabsorbable materials, improve stability of high mechanical properties, and provide a uniform degradation, assuring a good response of the human body to corrosion products. This fundamental study can provide a new direction in developing bioabsorbable materials with demanded properties for applications such as cerebrovascular stents or devices.