Plasma electrolytic oxidation of AZ31 magnesium stents for degradation rate control

Cardiovascular disease caused by the accumulation of atheroma plaques in the coronary arteries and the subsequent decrease in the blood flow through the affected vessel, known as atherosclerosis, is responsible for a high percentage of deaths worldwide. Angioplasty is practiced to treat atherosclero...

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Detalles Bibliográficos
Autores: Muñoz, Marta, Fernández, Juan Pablo, Torres, Belén, Pulido, Nuria, Zhang, Guangqi, Shanov, Vesselin, Moreno, Lara, Matykina, Endzhe
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/118082
Acceso en línea:https://hdl.handle.net/20.500.14352/118082
Access Level:acceso abierto
Palabra clave:620
AZ31 magnesium alloy
Biodegradable stent
Plasma electrolytic oxidation
Corrosion
Hydrogen evolution
Materiales
3312 Tecnología de Materiales
Descripción
Sumario:Cardiovascular disease caused by the accumulation of atheroma plaques in the coronary arteries and the subsequent decrease in the blood flow through the affected vessel, known as atherosclerosis, is responsible for a high percentage of deaths worldwide. Angioplasty is practiced to treat atherosclerosis which involves inserting a stent inside the occluded vessel to expand it and restore normal blood flow. In this work, temporary biodegradable stents made of AZ31 magnesium alloy have been fabricated using photo-chemical etching. The stents were coated via plasma electrolytic oxidation (PEO) technique. The radial strength of the stents was evaluated by cyclic compression, and the corrosion protection provided by the PEO coatings was studied by electrochemical and in vitro corrosion tests respectively. The stents showed an optimal maximum radial force of 0.147 N/mm and revealed elastic recuperation lower than 7 % of the total deformation after expansion. The applied PEO coating helped to control the corrosion of the magnesium alloy, delaying its initiation and, once it has started, decreased the degradation rate compared with the bare AZ31 samples. Thus, the stents treated with the PEO coatings developed in this research present promising results for their use as temporary medical devices used in angioplasty.