Nanocrystalline yttria was prepared by mechanical processing. A fraction was annealed in air at 473 K. Annealed and non-annealed powders were treated in Ar at temperatures between 700 and 1000 K, which induced a parabolic grain growth kinetics with an Arrhenius-like dependence on temperature. Grain growth is significantly slower in annealed powders with respect to non-annealed ones. This is related to oxygen chemical absorption during annealing in air and the consequent decrease of oxygen vacancies originally present in powders.
Nanocrystalline yttria: Grain growth depression by thermal annealing in air / Garroni, Sebastiano; Orrù, Roberto; Delogu, Francesco; Cao, Giacomo. - In: SCRIPTA MATERIALIA. - ISSN 1359-6462. - 104:(2015), pp. 33-36. [10.1016/j.scriptamat.2015.04.002]
Nanocrystalline yttria: Grain growth depression by thermal annealing in air
GARRONI, Sebastiano;
2015-01-01
Abstract
Nanocrystalline yttria was prepared by mechanical processing. A fraction was annealed in air at 473 K. Annealed and non-annealed powders were treated in Ar at temperatures between 700 and 1000 K, which induced a parabolic grain growth kinetics with an Arrhenius-like dependence on temperature. Grain growth is significantly slower in annealed powders with respect to non-annealed ones. This is related to oxygen chemical absorption during annealing in air and the consequent decrease of oxygen vacancies originally present in powders.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
