Corrosion of magnesium-aluminum alloys with Al-11Si/SiC thermal spray composite coatings in chloride solution

Depositions of Al-11Si coatings reinforced with 5, 15, and 30 vol.% SiC particles (SiCp) were performed onto AZ31, AZ80, and AZ91D magnesium alloys. The influence of substrate composition and SiCp proportion on the anti-corrosion properties of composite coatings was evaluated using DC and AC electro...

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Detalles Bibliográficos
Autores: Arrabal Durán, Raúl, Pardo Gutiérrez Del Cid, Ángel, Merino Casals, María Concepción, Mohedano Sánchez, Marta, Casajus, P., Matykina, Endzhe
Tipo de recurso: artículo
Fecha de publicación:2011
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/107713
Acceso en línea:https://hdl.handle.net/20.500.14352/107713
Access Level:acceso abierto
Palabra clave:66
Materiales
3312 Tecnología de Materiales
3303 Ingeniería y Tecnología Químicas
Descripción
Sumario:Depositions of Al-11Si coatings reinforced with 5, 15, and 30 vol.% SiC particles (SiCp) were performed onto AZ31, AZ80, and AZ91D magnesium alloys. The influence of substrate composition and SiCp proportion on the anti-corrosion properties of composite coatings was evaluated using DC and AC electrochemical measurements in 3.5 wt.% NaCl solution at 22 °C. The as-sprayed coatings were permeable to the saline solution, and galvanic corrosion occurred at the substrate/coating interface after immersion in the saline solution for a few hours. The addition of SiCp yielded coatings with higher porosity and less effectiveness against corrosion. The application of a cold-pressing post-treatment produced denser coatings with reduced surface roughness, improved hardness, and superior corrosion resistance. However, galvanic corrosion was observed after several days of immersion because of penetration of the 3.5 wt.% NaCl solution through the remaining pores in the coatings.