Low Temperature Degradation and Mechanical Properties of Alumina Reinforced Ceria-Zirconia by Colloidal Processing

10Ce-TZP base composites with 2.5, 5, 10 and 15 wt% alumina were fabricated by colloidal processing from slurries with 41 vol% solid load in order to investigate the effects of alumina in the final composites aging and mechanical properties. Alumina particle surface charge was modified with the addi...

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Detalles Bibliográficos
Autores: Tovar-Vargas, D., Ferrari, Begoña, Sánchez-Herencia, A. Javier, Anglada, M., Jiménez-Piqué, Emilio
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:10261/240788
Acceso en línea:http://hdl.handle.net/10261/240788
Access Level:acceso abierto
Palabra clave:Colloidal processing
Zirconia
Ceria
Alumina
Low Temperature Degradation
Descripción
Sumario:10Ce-TZP base composites with 2.5, 5, 10 and 15 wt% alumina were fabricated by colloidal processing from slurries with 41 vol% solid load in order to investigate the effects of alumina in the final composites aging and mechanical properties. Alumina particle surface charge was modified with the addition of 3 wt% of PAA. The resulting composites have high relative densities (∼ 99%) and homogeneous alumina distribution. The microstructure is refined by the alumina addition resulting in a tetragonal-monoclinic microstructure with monoclinic phase content diminishing with alumina concentration down to 16 vol% in 10Ce-15AlO composite. From the study of hydrothermal aging in autoclave steam at 134 °C and 2 bar pressure, it is concluded that all composites have very high resistance to low temperature degradation. At the same time, mechanical properties were investigated by measuring hardness, elastic modulus, strength and t-m transformation around Vickers and spherical indentations. The t-m transformation extension around imprints prevents the formation of Vickers indentations cracks, which indicates a high level of damage tolerance for all compositions. In particular, for 10Ce-15AlO composite, an excellent combination of hardness (∼10 GPa), strength (∼1400 MPa), damage tolerance, and resistance to low temperature degradation is achieved.