Alumina toughened zirconia reinforced with equiaxed and elongated lanthanum hexa-aluminate precipitates
نویسندگان
چکیده
Three different alumina sources (boehmite, aluminium nitrate and α-alumina particles) 12Ce-TZP powder containing 1 wt% lanthanum oxide were used to prepare 12Ce-TZP-based alumina-toughened-zirconia (ATZ) composites. The obtained ATZs had similar density phase composition, whereas the microstructures significantly different. Alumina-particle addition gave rise a typical ATZ microstructure consisting of equiaxial sub-micrometer zirconia phases, while hexa-aluminate was formed in large non-homogenously distributed precipitates (∼3.5 μm length). boehmite nitrate-based composites contained not only grains but also small-sized (∼1.2 length) that inter- transgranularly positioned matrix effectively promoted crack deflection toughening. In combination with higher t-ZrO2 transformability, boehmite-based indentation fracture resistance, strength reliability compared aluminium-nitrate alumina-particle based equivalents.
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ژورنال
عنوان ژورنال: Journal of The European Ceramic Society
سال: 2021
ISSN: ['0955-2219', '1873-619X']
DOI: https://doi.org/10.1016/j.jeurceramsoc.2021.09.038