Ceria‐stabilized tetragonal zirconia polycrystals were obtained by thermal treatment of amorphous powder prepared by the sol–gel method. Detailed XRD profile analysis was employed to study microstructural disorder and crystallite size and shape; in particular, no fluctuation of stoichiometry was found, the main cause of disorder being attributable to dislocations. Thermal expansion measurements were carried out by high‐temperature XRD at 294, 473, 673, 873, and 1073 K using silicon as an internal standard. Thermal expansion coefficients are anisotropic and changes in the stabilizer content have little effect on them. A mean value, αa= 10.6 × 10−6(K−1) and αc= 13.5 × 10−6(K−1), can be assumed for Zr1−xCexO2withxin