Structural, optical tuning, and mechanical behavior of zirconia toughened alumina through europium substitutions.

Abstract

The structural and optical features of zirconia toughened alumina (ZTA) due to the assorted range of Eu³⁺ substitutions are demonstrated. The characterization studies affirm the pivotal role of Eu³⁺ on the improved structural stability of ZTA and associated tetragonal zirconia (t-ZrO₂ ) → cubic zirconia (c-ZrO₂ ) transformation. Eu³⁺ prefers accommodation at the lattice sites of ZrO₂ and their gradual accumulation induces t- → c-ZrO₂ transition. Beyond the substitution limit, Eu³⁺ reacts with Al₂ O₃ to form EuAlO₃ . Optical studies validate typical Eu³⁺ emissions, and further, the emission spectrum also predicts the symmetry of Eu³⁺ coordination at the ZrO₂ lattice. Uniform distribution of ZrO₂ and Al₂ O₃ grains throughout the microstructures are evident from the morphological analysis. Further, the influence of Eu³⁺ on the enhanced mechanical stability of ZTA is ensured from indentation technique. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1170-1179, 2019.