Phase relations in the Al/sub 2/O/sub 3/-ZrO/sub 2/ system under various melt cooling conditions

The authors investigate the phase relations and the process of structure formation in specimens of the Al/sub 2/O/sub 3/-ZrO/sub 2/ system throughout the range of concentrations, quenched at various rates from the melt. X-ray investigations of the specimens and films were made and the crystal-optical characteristics of the specimens were determined. Differential thermal analysis was performed. The quantity of the metastable tetragonal modification ZrO/sub 2/ in the specimens depends on the rate of quenching of the melt and the concentration of zirconium dioxide, which determine the disperseness of the microstructure of the fused specimens.