Abstract
The development of ordered phases in the system ZrO2CaO was studied during prolonged heating of reactive powders derived from gels. The pure phase f{cyrillic}2 was obtained at 1250°C only with gels containing 24 m/o CaO which indicates that the correct composition of this phase is Ca6Zr19O44. This phase has rhombohedral symmetry, space group R3c, and is analogous to the f{cyrillic}2 phase in the HfO2CaO system. The pure phase f{cyrillic}1 (CaZr4O9) was obtained by heating gels containing 20 m/o CaO at 1180°C. This phase often appears as a precursor to the formation of the f{cyrillic}2 phase. At 1355±15°C the f{cyrillic}2 phase decomposes to a cubic ZrO2 solid solution and CaZrO3. At 1235±15°C the f{cyrillic}1 phase decomposes to a cubic ZrO2 solid solution and the phase f{cyrillic}2. The inability to synthesize a phase analogous to the phase f{cyrillic} (Ca2Hf7O16) in the HfO2CaO system can be explained by the low cation diffusivity in the ZrO2CaO system below 1150°C.
Original language | English (US) |
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Pages (from-to) | 459-465 |
Number of pages | 7 |
Journal | Materials Research Bulletin |
Volume | 17 |
Issue number | 4 |
DOIs | |
State | Published - Apr 1982 |
All Science Journal Classification (ASJC) codes
- General Materials Science
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering