Yang Quan1, Zhao Zhongmin1, Zhang Long1, et al. Preparation and Microstructural Evolution of Al2O3/ZrO2(4Y) Eutectic Composite Ceramic Large Bulk Plates[J]. Special Casting & Nonferrous Alloys, 2009,29(9):841-844.
Yang Quan1, Zhao Zhongmin1, Zhang Long1, et al. Preparation and Microstructural Evolution of Al2O3/ZrO2(4Y) Eutectic Composite Ceramic Large Bulk Plates[J]. Special Casting & Nonferrous Alloys, 2009,29(9):841-844.DOI:
By introducing high gravity into combustion synthesis
the Al2O3/ZrO2 (4Y) eutectic composite ceramic large bulk plates were prepared. The XRD analysis shows that the ceramic plates are composed of α-Al2O3
t-Al2O3 and m-ZrO2 phase under high gravity. SEM observation reveals that with increasing in high gravity
eutectic colony embedded by t-Al2O3 fiber is transformed from cellular structure into rod-like one
in which volumetric fraction and length-diameter ratio of eutectic colony are increased gradually. Relative density
the Vickers hardness and fracture toughness of the composite ceramics are increased with increasing in high gravity
and maximum values reach 97.8%
18.7GPa and 15.6MPa·m1/2
respectively
at 225g. High fracture toughness of the ceramics is attributed to the coupled effects of crack-deflection and crack-bridging toughening by rod-like eutectic colony with transformation toughening and micro-crack toughening by the fine spherically-shaped tetragonal ZrO2 crystals at inter-colony regions.