Spark plasma sintering of TiC with TiAly as sintering aid: Mechanisms and microstructures

TiC features an interesting combination of mechanical properties, high-temperature resistance, and lightness, making it an excellent candidate for several applications in harsh environments. However, its sintering to obtain bulk components is extremely challenging. Herein, we show that titanium alum...

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Detalles Bibliográficos
Autores: Rizzi, A., García-Fernández, M., Rodríguez Barbero, Miguel Ángel, De Bona, E., Moreno, Rodrigo, Biesuz, M.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/381681
Acceso en línea:http://hdl.handle.net/10261/381681
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85202575301&doi=10.1016%2fj.oceram.2024.100661&partnerID=40&md5=0a00d7ada415e5f01bbc7e0709d2c6cb
Access Level:acceso abierto
Palabra clave:Sintering
SPS
TiAl
TiC
UHTCs
Descripción
Sumario:TiC features an interesting combination of mechanical properties, high-temperature resistance, and lightness, making it an excellent candidate for several applications in harsh environments. However, its sintering to obtain bulk components is extremely challenging. Herein, we show that titanium aluminide is a promising sintering aid for TiC (5, 10, and 20 vol% were investigated). The aluminide allows the formation of a nearly fully dense component at 1350 °C by spark plasma sintering under 80 MPa. The aluminide forms a grain boundary secondary phase that promotes the Ti diffusion: Ti from TiC can be dissolved within the TiAly at the neck center and precipitate at the neck surface, while C can easily diffuse through the TiC lattice. Higher temperatures cause the extrusion of the aluminide out of the SPS die and its reaction with oxygen impurities. The final microstructure is constituted by nearly pure TiC with isolated alumina pockets at the triple points. © 2024 The Authors