The System Zirconia‐Scandia

The system zirconia‐scandia was investigated using X‐ray diffraction analysis, differential thermal analysis, metallographic analysis, and melting point studies. Results reveal the monoclinic α 1 phase (0 to 2 mol% Sc 2 O 3 ), the tetragonal α 2 ’phase (5 to 8% Sc 2 O 3 ), the rhombohedral β phase (9 to 13% Sc 2 O 3 ), the rhombohedral γ phase (15 to 23% Sc 2 O 3 ), the rhombohedral δ phase (24 to 40% Sc 2 O 3 ), and the cubic % phase (77.5 to 100% Sc 2 O 3 ). The monoclinic α 1 phase and the tetragonal α 2 ’phase were found to transform to the tetragonal α 2 phase over a wide temperature range depending on composition. The β, γ, and α phases transformed to a cubic phase at temperatures of %600 % , 1100 % , and 1300 % C, respectively. A maximum melting point of %2870 % C was found at %10% Sc 2 O 3 and a eutectic at %2400 % C at 55% Sc 2 O 3 .