Abstract
Mixtures of rare-earth zirconates and aluminates containing Y or Y + Gd that form a two-phase garnet–fluorite mixture exhibit much slower sintering than pure fluorite at 1400°C. An equivalent Y-free, Gd-containing composition that forms a perovskite aluminate instead of garnet showed faster densification after the metastable garnet decomposes. At 1500°C, the Y-free sample also showed the fastest initial sintering rate, whereas there was more divergence in the sintering rate for the samples containing Y + Gd. The zirconate–aluminate with equimolar Y + Gd shows the slowest densification at 1500°C and retains ∼25% porosity after 250 h. The results highlight possibilities for designing compliant thermal barrier coatings that can retain significant porosity at 1400°C or higher.
Original language | English (US) |
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Pages (from-to) | 4519-4525 |
Number of pages | 7 |
Journal | Journal of the American Ceramic Society |
Volume | 106 |
Issue number | 8 |
DOIs | |
State | Published - Aug 2023 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2023 The Authors. Journal of the American Ceramic Society published by Wiley Periodicals LLC on behalf of American Ceramic Society.
Keywords
- aluminates
- rare-earth oxides
- sintering
- thermal barrier coatings
- zirconates