In Situ study of Nucleation of Zirconia in an MgO-Al^sub 2^O^sub 3^-SiO^sub 2^ Glass

Crystalline nucleation is investigated during the dynamical heat treatment of a ...-MgO-...-... glass by high-temperature Zr K-edge X-ray absorption near-edge spectroscopy. In the parent glass, the Zr coordination number is higher than in most glasses, explaining the structural instability of Zr during thermal treatment. The Zr local structure is modified at 30...C above the nucleation onset. Crystalline nucleation is characterized by the formation of peculiar nano-... particles, which are stable until completion of the thermal treatment. These nano-... particles are stable during the elaboration of glass-ceramics, without any ... remaining in the glassy matrix of the final material. (ProQuest: ... denotes formulae/symbols omitted.)