Alumina/molybdenum nanocomposites obtained by colloidal synthesis and spark plasma sintering

[EN] Alumina/molybdenum nanocomposites were prepared by colloidal synthesis from alumina powder and molybdenum (V) chloride using ethanol as dispersion medium. Modified alumina was calcined at 450 ¿C in air atmosphere to remove chlorides, and then treated in a tubular furnace at 850 ¿C under Ar/H2 t...

Descripción completa

Detalles Bibliográficos
Autores: Fernández-González, Daniel, Suárez-Menéndez, Marta, Piñuela-Noval, Juan, Díaz, Luís Antonio, Gómez-Rodríguez, Carlos, García Quiñonez, Luís V., Fernández-Valdés, Adolfo, Borrell Tomás, María Amparo|||0000-0003-4292-4538
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/209542
Acceso en línea:https://riunet.upv.es/handle/10251/209542
Access Level:acceso abierto
Palabra clave:Ceramics
Composite materials
Sintering
Mechanical properties
Spark plasma sintering
Alumina
Cermets
CIENCIA DE LOS MATERIALES E INGENIERIA METALURGICA
Descripción
Sumario:[EN] Alumina/molybdenum nanocomposites were prepared by colloidal synthesis from alumina powder and molybdenum (V) chloride using ethanol as dispersion medium. Modified alumina was calcined at 450 ¿C in air atmosphere to remove chlorides, and then treated in a tubular furnace at 850 ¿C under Ar/H2 to reduce the MoO3 formed in the previous stage and obtain Al2O3 with molybdenum nanoparticles on the surface. Three different molybdenum contents were proposed (1, 5 and 10 wt % Mo), and pure alumina was used as reference, that were sintered by spark plasma sintering (SPS) under vacuum atmosphere at 1400 ¿C for 3 min with an applied pressure of 80 MPa. Composites were characterized by microstructure, hardness, toughness, and three-point bending test. The presence of molybdenum nanoparticles resulted in a fine-grained structure promoted by the presence of molybdenum at grain boundaries and triple points, as well as by the utilization of the SPS equipment. Hardness is at least a 20% greater and fracture toughness 30% larger in the composites than in the monolithic alumina.