Fig. 1. XRD patterns of the ceramics sintered under different conditions: (a) hot-pressed at 1300 °C, (b) hot-pressed at 1500 °C, and (c) SPS-ed at 1300 °C. The Si was added as internal marker.

Fig. 2. Phase diagram of the ZrO₂–CeO_1.5 system.¹⁷

Fig. 3. SEM micrograph of the 8 mol% CeO₂ stabilized ZrO₂ ceramic sintered by SPS.

Fig. 4. TEM micrograph of the 8 mol% CeO₂ stabilized ZrO₂ ceramic sintered by SPS.

Fig. 5. Detail of a monoclinic grain of the 8 mol% CeO₂ stabilized ZrO₂ ceramic sintered by SPS.

Fig. 6. TEM micrographs and EDS spectra taken from different grains in the 8 mol% CeO₂ stabilized ceramic sintered by SPS. The analysis results of the labelled positions are summarized in Table 2.

Sintering conditions, densities and phase assembly of the sintered samples

^aC_ss: Zr–Ce–O cubic solid solution; t: tetragonal; s: strong; m: medium; w: weak; tr: trace.

EDS results of different point analysis at the locations indicated in Fig. 6

^aZr ions are assumed to retain their tetravalent state.