Reactivity of chromium-based pigments in a porcelain glaze

Publication date: Available online 23 October 2018Source: Comptes Rendus PhysiqueAuthor(s): Louisiane Verger, Olivier Dargaud, Gwenaëlle Rousse, Laurent CormierAbstractThis paper presents a comprehensive investigation at the microscopic scale of various pigments composed of chromium from the French ‘Manufacture de Sèvres’ to establish the origin of color in glazes. Electron microscopy coupled with X-ray diffraction allows the determination of the microstructure and composition of the crystalline phases after firing. X-ray absorption spectroscopy reveals subtle changes in the medium-range ordering around Cr with high spatial resolution, in the pigment grain or at the pigment/glass interface. Principal results indicate systematic and common changes whatever the pigment types: (i) Cr-enrichment for the final crystals, that controls the coloration of the glaze, (ii) migration of specific elements such as Al or Zn from the pigments to the amorphous part of the glaze, and (iii) crystallization of anorthite in the near proximity of the altered Cr-bearing crystalline pigments.RésuméDivers pigments composés de chrome et synthétisés à la Manufacture de Sèvres sont étudiés dans cet article pour comprendre l'origine de la couleur des décors de porcelaine. La microscopie électronique couplée à la diffraction des rayons X permet de déterminer la microstructure et la composition des phases cristallines présentes après la cuisson du décor. Des mesures d'absorption des ...
Source: Comptes Rendus Physique - Category: Physics Source Type: research