Characterization of Y2O3, CeO2 and Y2O3+CeO2 Doped FGM Tetragonal ZrO2 Ceramics by Spark Plasma Sintering
In this study, 2 mol% Y2O3 (2Y), 1 mol% Y2O3+6 mol% CeO2 (1Y6Ce) and 12 mol% CeO2 (12Ce)-doped tetragonal ZrO2 ceramics were made by spark plasma sintering (SPS) for 2 min at 1450°C under a pressure of 60 MPa. The influence of stabilizers on microstructure, phase and mechanical properties of the ZrO2 ceramics was investigated. After sintering, the 2Y and 1Y6Ce were intact, containing full tetragonal ZrO2 phase on the polished cross-sectioned surface, whereas the 12Ce exhibited macro-cracks, corresponding to a large amount of monoclinic ZrO2 phase. Graded microstructure and mechanical properties were observed in the 1Y6Ce, showing a gradually decreased fracture toughness from sample edge towards centre, together with the slight decreased hardness. The 2Y had a uniform microstructure and mechanical properties. The formation of the graded structure and toughness profile was explained in terms of the gradual CeO2 reduction to Ce2O3 in the Y2O3+CeO2 doped ZrO2 ceramics.
Marc Anglada et al.
S. G. Huang et al., "Characterization of Y2O3, CeO2 and Y2O3+CeO2 Doped FGM Tetragonal ZrO2 Ceramics by Spark Plasma Sintering", Key Engineering Materials, Vol. 333, pp. 231-234, 2007