Defects and phase transitions in yttria- And scandia-doped zirconia
Internal friction (IF) experiments were performed on the systems ZrO 2 (8-12 mol%)-Y2O3, and ZrO2 (9-12 mol%)-Sc2O3. The following features were found: (i) an IF peak around 500 K in both systems which is assigned to the hopping of trapped oxygen vacancies (ΔH=1.2-1.3 eV); (ii) in polycrystalline ma...
| Authors: | , , , , , |
|---|---|
| Format: | article |
| Status: | Published version |
| Publication Date: | 2004 |
| Country: | Argentina |
| Institution: | Consejo Nacional de Investigaciones Científicas y Técnicas |
| Repository: | CONICET Digital (CONICET) |
| Language: | English |
| OAI Identifier: | oai:ri.conicet.gov.ar:11336/72459 |
| Online Access: | http://hdl.handle.net/11336/72459 |
| Access Level: | Open access |
| Keyword: | Cation Diffusion Internal Friction Phase Transitions Scandia-Stabilized Zirconia Ysz https://purl.org/becyt/ford/1.3 https://purl.org/becyt/ford/1 |
| Summary: | Internal friction (IF) experiments were performed on the systems ZrO 2 (8-12 mol%)-Y2O3, and ZrO2 (9-12 mol%)-Sc2O3. The following features were found: (i) an IF peak around 500 K in both systems which is assigned to the hopping of trapped oxygen vacancies (ΔH=1.2-1.3 eV); (ii) in polycrystalline materials a high temperature damping background, which is related to cation diffusion; (iii) an order/ disorder phase transition at 1450 K in ZrO2-12 mol%Y 2O3; and (iv) in ZrO2-Sc2O 3 a ferroelastic ↔ ferroelectric phase transition at 750 K from the rhombohedral to the cubic phase. Cation diffusion experiments in ZrO 2-Sc2O3 revealed an activation enthalpy for Zr diffusion of 5.3 eV indicating that short- and long-range cation transport is governed by one type of cation diffusion process. © 2004 Elsevier B.V. All rights reserved. |
|---|