Metastable forms of the tetragonal phase in compositionally homogeneous ZrO2-CaO nanopowers

I.O. FÁBREGAS; D.G. LAMAS; R.O. FUENTES; M.E. FERNÁNDEZ DE RAPP; N.E. WALSÖE DE RECA; A.F. CRAIEVICH

2004 Activity Report of the Brazilian Synchrotron Light Laboratory

Laboratorio Nacional de Luz Sincrotron (LNLS)

Año: 2005 p. 396 - 396

1518-0204

In this work, the crystal structure of nanocrystalline ZrO2-CaO solid solutions, synthesized by a nitrate-glycine gelcombustion route, was investigated by means of synchrotron powder X-ray diffraction. The tetragonal/cubic compositional boundary was determined by monitoring the variation of weak reflections of the tetragonal phase related to the displacement of oxygen atoms from their ideal positions in the cubic phase. Our results show that the use of synchrotron radiation coupled to a high-intensity configuration allowed to distinguish between the t"-form of the tetragonal phase from the cubic phase. The tetragonal/cubic compositional boundary resulted of (15 ± 1) mol% CaO.