The AL₂O₃-HFO₂-Y₂O₃ Phase Diagram.
IV. Vertical Sections

Abstract

For better presentation of the AL₂O₃-HfO₂-Y₂O₃ phase diagram over wide ranges of temperatures and concentrations, three vertical sections are plotted to show interactions in the ternary system. The Y₂O₃ bisector shows the Y₂O₃-rich region of the AL₂O₃-HFO₂-Y₂O₃ phase diagram and explains the mechanism of X ⇆ Н ⇆ А ⇆ B phase transformations for Y₂O₃ solid solutions. The 10 mol.% HfO₂ (10H) isopleth shows the AL₂O₃-HfO₂-Y₂O₃ structure in the region adjacent to the AL₂O₃–Y₂O₃ binary bounding system. The HfO₂ bisector shows the structure of the HfO₂–rich region and the mechanism of F ⇆ T ⇆ M phase transformations for HfO₂ solid solutions.