ESTUDO DO SISTEMA LaAl1 FexO3 PARA APLICAÇÃO COMO PIGMENTO CERÂMICO

Abstract

The system LaAl1-xFexO3 was synthesized through the Modid Pechini Method (MPM) and solid state reaction (SSR) to evaluate its applicability as a ceramic pigment. The MPM synthesis was carried out with metallic ion nitrates and thermal treatment at 910 °C for 4 hours, while the SSR syntheses comprised metallic ion oxides and thermal treatment at 1400 °C for 4 hours. The pigments obtained through MPM were characterized through X-ray diraction, structural renement through the Rietveld method, Mossbauer spectroscopy, eld eect scanning electronic microscopy, UV-Vis diuse re ectance and analysis of colorimetric values through the CIEL*a*b*. The SSR obtained pigments were not submitted to Mossbauer spectroscopy and the Rietveld Method structural renement analyses. MPM synthesized pigments were obtained with perovskite as the only phase, crystallizing in the rhombohedric crystalline system with values 0:00 x 0:80, and values x > 0:80 in the orthorhombic system. The SSR revealed the possible presence of secondary phases in the formation of the pigment crystalline structure and the values x 0:60 crystallized in the rhombohedric system, and values x > 0:60 in the orthorhombic system. The pigments obtained presented color between green and orange/red. Their use in ceramic pieces was also evaluated.