Two-step strategy for improving the tribological performance of Si3N4 ceramics: Controlled addition of SiC nanoparticles and graphene-based nanostructures

The tribological behaviour of silicon nitride (Si3N4) ceramics is investigated using a two-step strategy. A set of ceramic composites containing silicon carbide nanoparticles (SiCn) is developed and, subsequently, graphene-based fillers are added to the Si3N4/SiC composite with the best tribological...

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Detalles Bibliográficos
Autores: Llorente, Javier, Ramírez, Cristina, Belmonte, Manuel
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/240354
Acceso en línea:http://hdl.handle.net/10261/240354
Access Level:acceso abierto
Palabra clave:Tribology
Friction
Wear
Ceramic composites
Graphene
Descripción
Sumario:The tribological behaviour of silicon nitride (Si3N4) ceramics is investigated using a two-step strategy. A set of ceramic composites containing silicon carbide nanoparticles (SiCn) is developed and, subsequently, graphene-based fillers are added to the Si3N4/SiC composite with the best tribological performance. The friction coefficient and the wear rate of Si3N4 are reduced up to 22 % and 40 %, respectively, when a 10 vol.% of SiCn is incorporated into the ceramic matrix due to its improved mechanical response. Si3N4/SiC composites containing 11 vol.% of graphene nanoplatelets (GNPs) or reduced graphene oxide sheets (rGOs) are analysed under isooctane lubrication and dry testing. rGOs composite leads to an important decrease of the friction coefficient (50 %) under lubricated conditions, and an enhancement of the wear resistance (44 %) under dry sliding tests, as compared to the reference Si3N4/SiC. The best performance of rGOs composite is due to the nature of the lubricating tribofilm and its excellent toughness.