Raman/Cr3+ Fluorescence Mapping of Melt-Grown Al2O3/GdAlO3 Eutectics

Gwenaël Gouadec (1) , Philippe Colomban (1) , Nicolas Piquet (2) , Marie-France Trichet (3) , Léo Mazerolles (3)

1 LADIR - Laboratoire de Dynamique Interactions et Réactivité
2 ONERA - The French Aerospace Lab [Châtillon]
3 ICMPE - Institut de Chimie et des Matériaux Paris-Est

The paper reports on the Raman/fluorescence study of melt-grown Al2O3/GdAlO3 eutectic composites. Raman bands from the Α-alumina and gadolinium perovskite phases identified by X-ray diffraction were systematically observed together in the domains optically visible, even when the latter were much larger than the Raman probe. This suggests a more complex interlocking pattern than appearing on SEM or optical microscopy images. The polarization of alumina and GdAlO3 Raman bands evidenced the preferential orientation of Al2O3 phase with respect to the sample growth direction, in agreement with TEM results. In addition, the position of chromium impurity fluorescence bands was used to map the residual stress in alumina phase. It is a compression in the 200-300 MPa range.

Mots clés: Stress mapping; Electron microscopy; Raman Spectroscopy; alumina; Perovskites; eutectics; Gadolinium oxide

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Gwenaël Gouadec, Philippe Colomban, Nicolas Piquet, Marie-France Trichet, Léo Mazerolles. Raman/Cr3+ Fluorescence Mapping of Melt-Grown Al2O3/GdAlO3 Eutectics. Journal of the European Ceramic Society, 2005, 25, pp.1447-1453. ⟨hal-00124703⟩