Crystallization and Polymorphic Phase Transitions in Zirconia-Toughened Alumina Systems Induced by Dy3+/Gd3+ Cosubstitutions
| Autor: | Sanjeevi Kannan, Rugmani Meenambal, V. Ponnilavan |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Phase transition
Materials science Zirconia Toughened Alumina Composite number Rare earth Modulus 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences 0104 chemical sciences law.invention Crystallography law Lattice (order) General Materials Science Crystallization 0210 nano-technology Material properties |
| Zdroj: | Crystal Growth & Design. 18:4449-4459 |
| ISSN: | 1528-7505 1528-7483 |
| DOI: | 10.1021/acs.cgd.8b00435 |
| Popis: | The substitution of rare earth elements in zirconia-toughened alumina (ZTA) to expand the resultant material properties forms a crux of the investigation in recent years. In this work, the simultaneous substitutions of Gd3+ and Dy3+ in ZTA and the subsequent variation in the structural, mechanical, and magnetic imaging characteristics are demonstrated. A detailed structural analysis verified the combined occupancy of Gd3+/Dy3+ at the ZrO2 lattice, while the α-Al2O3 component of the composite remains unperturbed. However, the free Gd3+ exceeding the substitution limit reacts with Al2O3 to yield GdAlO3. Further, the optimum level of Gd3+/Dy3+ in ZTA exhibited superior mechanical features with hardness and Young’s modulus of 18 and 251 GPa, respectively. Dy3+ presence persuaded emission in the visible region while Gd3+/Dy3+ combined in ZTA unveiled improved T1 and T2 magnetic resonance imaging features with relaxivity values of r1 = 22 and r2 = 39 mM–1 s–1. In addition, the strong resistance of ZTA against h... |
| Databáze: | OpenAIRE |
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