| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1578413 | Materials Science and Engineering: A | 2011 | 7 Pages |
Multiphase (MP) monoclinic and cubic Y2O3 nanoparticles, 40 nm in diameter, were densified by spark plasma sintering for 5–15 min and100 MPa at 1000 °C, 1100 °C, and 1500 °C. Densification started with pressure increase at room temperature. Densification stagnated during heating compared to the high shrinkage rate in cubic single-phase reference nanopowder. The limited densification of the MP nanopowder originated from the vermicular structure (skeleton) formed during the heating. Interface controlled monoclinic to cubic polymorphic transformation above 980 °C led to the formation of large spherical cubic grains within the vermicular matrix. This resulted in the loss of the nanocrystalline character and low final density.
► Multiphase monoclinic and cubic Y2O3 nanoparticles were densified by spark plasma sintering. ► Densification stagnated compared to the high shrinkage rate in cubic single-phase nanopowder. ► Vermicular structure formed during heating limited densification of the multiphase nanopowder. ► Large cubic grains formed by polymorphic transformation led to the loss of the nano-crystallinity.
