3. Physical properties of zirconia

Zirconia has a number of interesting properties. In addition to the mechanical properties already presented in the previous paragraph (see table 3 ), zirconia has a very low thermal conductivity compared with most other oxides (figure 10 ). This property is put to good use in the case of thermal barriers that protect the metal surfaces of turbine engine components from high-temperature gases; zirconia enables these metal surfaces to be thermally insulated. Recent studies show that cubic zirconia is generally the best thermal insulator, and that the use of large heterovalent ions, such as La ³⁺ ...