Dynamic aspects of cerium dioxide sintering: HT-ESEM study of grain growth and pore elimination

Renaud Podor (1) , Nicolas Clavier (1) , Johann Ravaux (1) , Laurent Claparede (1) , Nicolas Dacheux (1) , Didier Bernache-Assollant (2, 3, 4)

1 ICSM - UMR 5257 - Institut de Chimie Séparative de Marcoule
2 LPMG-EMSE - Laboratoire des Procédés en Milieux Granulaires
3 IFRESIS - Institut Fédératif de Recherche en Sciences et Ingénierie de la Santé
4 LINA-ENSME - Laboratoire Interdisciplinaire des Nanoparticules Aérosolisées

Sintering of CeO2 is studied in situ by high temperature scanning environmental microscopy (HT-ESEM) at T = 1400 °C. The morphological modifications of a single grains population are recorded for 6 h. Kinetic parameters are extracted from image series. The local grain growth determined from the single population studied in situ is compared to the general grain growth obtained by classical ex situ technique. Using HT-ESEM for sintering study is validated. The grain boundary velocities range between 0 and 5 μm h−1, with a mean value of about 1 μm h−1. The migration of the intragranular surface pores is described. Their velocities range between 0.4 and 1.2 μm h−1 and depend on pore diameters: the smaller the pore, the faster the pore velocity. The time required to fill a pore that arises at the sample surface is determined as a function of pore diameter. The time for pore elimination dependence with the pore diameters is also established.

Mots clés: Sintering; Grain growth; Grain boundaries; Electron Microscopy; CeO2

Domaines: Génie des procédés; Matériaux

Renaud Podor, Nicolas Clavier, Johann Ravaux, Laurent Claparede, Nicolas Dacheux, et al.. Dynamic aspects of cerium dioxide sintering: HT-ESEM study of grain growth and pore elimination. Journal of the European Ceramic Society, 2012, 32 (2), pp.353-362. ⟨10.1016/j.jeurceramsoc.2011.08.032⟩. ⟨hal-00638087⟩