Transmission Electron Microscopy of Annealed ZrO 2 +8 Mol% Sc 2 O 3

The influence of heat treatment (800°C for 200 h) on the micro‐structure of 8 mol% Sc 2 O 3 ‐ZrO 2 was investigated by XRD and TEM. The starting material was initially characterized and found to contain predominantly cubic‐fluorite phase grains, with <5% of the grain containing the rhombohedral β phase. The β phase was positively identified by the analysis of electron diffraction pattern and by quantitative energy dispersive X‐ray analysis. On aging, the relative amount of β phase was found to increase to about 15 to 20% by XRD measurement; this was confirmed by TEM observation. The orientation relation between the different variants of the β phase within a grain was determined to be (100) r ||(010) r , and the geometrical arrangement of these variants within the grain was deduced using a 2 1 / 2 D imaging electron microscopy technique.