The use of image analysis for sintering investigations: The example of CeO2 doped with TiO2

This paper deals with the use of automatic image analysis to provide access to the morphological parameters of the microstructure during the sintering of ceria. Some specific techniques of image processing have been required and performed to automatically measure the change in the specific surface area, the integral of mean curvature per unit volume, the contiguity and the grain size distribution. The diffusional paths, the kinetics of densification and the mobility of the grain boundaries were determined. A value of about 2 was obtained for the grain size exponent. The densification at 1300 °C and probably at 1200 °C is governed by the volume diffusion of the slowest species. Moreover, the use of a TiO2 dopant makes it possible to control the migration of the CeO2 grain boundaries and thus to limit grain growth.