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

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.