Alumina Toughened Zirconia Nanocomposite Incorporating Al₂O₃ Whiskers

Abstract

We investigated the Vickers hardness and fracture toughness of an Al2O3(n) + 70 wt% ZrO2 (TZ‐3Y)n nanocomposite with addition of 2.5 wt% Al2O3 whiskers. Densities greater than 95% were reached after conventional sintering at 1500°C. The fracture toughness was increased 62% over pure Al2O3. Microcracking and crack deflection can be the mechanisms responsible to improve the fracture toughness. The use of ATZ composites with a low percent of whiskers can be a promising biomedical material for medical and dental applications given its large increase in fracture toughness over pure alumina and the observed relief from aging issues of zirconia.

High temperature performance of mullite whisker-reinforced ZTA

“…Studies have also shown that crystalline mullite reacts with water vapor at 1100℃ through the following reaction at grain boundaries. 39 This may lead to degradation of mullite in the ZTA w . Single crystal mullite inclusions should not be affected by this reaction; however, large diameter whiskers formed by the fusion of aligned smaller diameter whiskers may be prone to degradation through reaction (4).…”

Ceramic Toughening Strategies for Biomedical Applications

“…Except for these basic forms of ZrO 2 -Al 2 O 3 materials, the shapes of both components could be altered, or other metal compounds could be added, to achieve better toughening effect. Aguilar-Elguézabal and Bocanegra-Bernal (2013) investigated the fracture toughness of an Al 2 O 3 (n)-70 wt% ZrO 2 (ZrO 2 with 3 mol% yttria, TZ-3Y)n nanocomposite with addition of 2.5% Al 2 O 3 whiskers. The fracture toughness was enhanced 62, 28, and 7% over pure Al 2 O 3 , the composite without additions of whiskers, and pure TZ-3Y for medical applications, respectively.…”

“…Toughening based on ZrO 2 -Al 2 O 3 system or mica glass ceramics ( Gali and Kumar, 2019 ), and using ion-exchange (chemical methods) tends to preserve excellent esthetics, while adding colorful fillers like AgNPs ( Fujieda et al, 2012 ) would affect ceramic color. For non-esthetic demanding applications, high toughness is the first consideration, which is fine achieved by fiber/whisker-shape ( Aguilar-Elguézabal and Bocanegra-Bernal, 2013 ) or nanocarbon adding ( Siddiqui et al, 2018 ).…”

Spark Plasma Sintering and Characterization of Graphene Platelet/Ceramic Composites

“…[3] To overcome this problem, various strategies and processing approaches have been proposed. [9,10] Carbon fillers, such as carbon nanotubes (CNTs) and carbon fibers have been extensively studied as strong reinforcements due to their remarkable Young's modulus. [9,10] Carbon fillers, such as carbon nanotubes (CNTs) and carbon fibers have been extensively studied as strong reinforcements due to their remarkable Young's modulus.…”

“…[4][5][6][7][8] Among them, the addition of secondary strong and tough nanofillers has become popular for a significant improvement in the mechanical properties of the ceramic matrices can be achieved by introducing a small percentage of these nanofillers. [9,10] Carbon fillers, such as carbon nanotubes (CNTs) and carbon fibers have been extensively studied as strong reinforcements due to their remarkable Young's modulus. However, the high cost of these carbon fillers make them less competitive when mass production of related composites is considered.…”