Recubrimientos de vidrios de fosfatos de calcio sobre circonas

Abstract

The results obtained in the preparation and micro-structural characterization of the calcium phosphate glasses coating on two different zirconia substrates are discussed. The thermal treatments were carried out at 1 100 °C for 2 h in air. The materials were characterized by scanning electron microscope (SEM), environment scanning electron microscope (ESEM), X-ray
diffraction (XRD) and microanalysis by energy-dispersive-spectrometer (EDS) coupled to SEM. Also, the changes occurred at the material surfaces after two weeks in simulated body fluid (SBF) were studied. The observations by SEM showed a good deposition of the glass coatings on both zirconia substrates. The microanalysis results by EDS demonstrated the diffusion of magnesium from
zirconia structure to glass for magnesia partially stabilized zirconia and the diffusion of calcium from glass to substrate for yttrium partially stabilized zirconia was also observed. The formation of new phases associated with crystallization of glass and the diffusion of calcium and magnesium provide a certain complexity to XRD patterns interpretations. After two weeks in SBF, the observations by ESEM and SEM revealed that significative changes at the surfaces of the materials were occurred. The changes were related with the glass degradation by effect of the SBF solution. No formation of apatite layer was observed.