Conversion from beta-Ce2O3 center dot 11Al(2)O(3) to alpha-Al2O3 in tetragonal ZrO2 matrix

Composites of beta -Ce2O3. 11Al(2)O(3) and tetragonal ZrO2 fabricated by a reductive atmosphere sintering of mixed powders of CeO2, ZrO2 (2 mol % Y2O3 ), and Al2O3. The composites had microstructures composed of elongated grai ns of beta -Ce2O3. 11Al(2)O(3) in a Y-TZP matrix. The beta -Ce2O3. 11Al(2)O (3) decomposed to alpha -Al2O3 and CeO2 by annealing at 1500 degreesC for 1 h in oxygen. The elongated single grain of beta -Ce2O3. 11Al(2)O(3) divide d into several grains of alpha -AI(2)O(3) and ZrO2 doped with Y2O3 and CeO2 . High-temperature bending strength of the oxygen-annealed alpha -Al2O3 com posite was comparable to the beta -Ce2O3 . 11AI(2)O(3) composite before ann ealing.