SciELO - Scientific Electronic Library Online

 
vol.54 issue330Porous mullite obtained using silica from rice husk and aluminum acetateDrying additives for refractory castables: aluminum powder and polymeric fibers author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Cerâmica

Print version ISSN 0366-6913

Abstract

PESSOA, R. C.; CERQUEIRA, M.; NASAR, R. S.  and  YOSHIDA, I. V. P.. Synthesis of stabilized zirconia without dopants. Cerâmica [online]. 2008, vol.54, n.330, pp. 253-258. ISSN 0366-6913.  http://dx.doi.org/10.1590/S0366-69132008000200016.

ZrO2-SiO2 powders were synthesized through Pechini's method starting with D4Vi, PMS and zirconium citrate. The complex polymer was decomposed to form different phases at high temperatures. During the resin decomposition, the phase transformation from monoclinic to tetragonal zirconia was detected by thermal analysis. The crystallization and the diffusion process of Si and Zr were analyzed by X-ray diffraction, XRD, scanning electron microscopy and microanalysis by EDS. Tetragonal zirconia at 1000 ºC, monoclinic zirconia at 1200 ºC and monoclinic zirconia with cristobalite silica from 1300 º to 1400 ºC were formed. From 1000 ºC to 1300 ºC a diffuse amorphous band was related to the silica phase. The mapping of Kα line of Zr and Si showed low diffusion of Si into the ZrO2 structure. The kinetics of crystallization formed macroparticles of silica and small particles of zirconia. A diffusion interface between SiO2 and ZrO2 to form ZrSiO4 phase was not observed, confirmed by XRD.

Keywords : Pechini method; zirconia stabilization; EDS microanalysis.

        · abstract in Portuguese     · text in English     · pdf in English