Abstract
Structural changes resulting from sintering and phase transformation limit the high-temperature durability of ZrO2-based thermal barrier coatings (TBCs). The objective of this study was to investigate the use of Gd2O3 as a stabilizer for ZrO2-based TBC compositions. The influence of Gd2O3 concentration (4-20 mol.%) on the sintering and phase stability of plasma-sprayed ZrO2 powders was investigated and the data were compared with those for the state-of-the-art Y2O3-stabilized ZrO2. At an equivalent concentration (4 mol.%), Gd2O3-stabilized ZrO2 sintered more slowly but had a lower resistance to destabilization of the metastable tetragonal (t′) phase, when compared to Y2O3-stabilized ZrO2. The thermal conductivity of Gd2O3-stabilized ZrO2 was lower than that of Y2O3-stabilized ZrO2. Factors influencing the sintering and phase transformation of plasma-sprayed Gd2O 3-stabilized ZrO2 are discussed.
Original language | English |
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Pages (from-to) | 1615-1621 |
Number of pages | 7 |
Journal | Acta Materialia |
Volume | 54 |
Issue number | 6 |
DOIs | |
State | Published - Apr 2006 |
Externally published | Yes |
Funding
This work was supported by the Air Force Research Laboratory, Materials and Manufacturing Directorate, TOPS DO Contract Number 0032. Thermal diffusivity experiments were performed at the Oak Ridge National Laboratory, High Temperature Materials Laboratory (HTML) through the HTML User Program.
Funders | Funder number |
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Materials and Manufacturing Directorate | |
Air Force Research Laboratory |
Keywords
- Phase transformation
- Plasma spraying
- Sintering
- Thermal barrier coating
- Thermal conductivity