Mechanical synthesis of nanostructured Y2Ti2O7 pyrochlore oxides

E. Simondon (1, 2) , P-F Giroux (1, 2) , L. Chaffron (1, 2) , A. Fitch (3) , P. Castany (4) , T. Gloriant (4)

1 Université Paris-Saclay
2 SRMA - Service des Recherches Métallurgiques Appliquées
3 ESRF - European Synchrotron Radiation Facility
4 ISCR - Institut des Sciences Chimiques de Rennes

Pyrochlore-type Y2Ti2O7 powders were successfully synthesized by mechanical milling. Nanosized powders of Y2O3 and TiO2 are milled to form an amorphous mixture of Y2Ti2O7 containing a small quantity of crystallized fluorite structure and initial constituents. The desired fully crystallized pyrochlore phase is obtained from this mixture through heat treating at 900 degrees C. In situ X-ray Diffraction by Synchrotron radiation investigations reveal that this transformation takes pace through a first step of crystallization into a fluorite-like structure at 800 degrees C. The formation of the pyrochlore structure occurs around 900 degrees C. The obtained product is a nanostructured pyrochlore powder of which can be integrated in the manufacturing process of oxide dispersion strengthened steels.

Mots clés: Pyrochlore oxide; Mechanical milling; Nanostructure; X-ray diffraction (XRD); Synchrotron radiation

Domaines: Chimie

E. Simondon, P-F Giroux, L. Chaffron, A. Fitch, P. Castany, et al.. Mechanical synthesis of nanostructured Y2Ti2O7 pyrochlore oxides. Solid State Sciences, 2018, 85, pp.54-59. ⟨10.1016/j.solidstatesciences.2018.09.006⟩. ⟨hal-01935361⟩