Metallic components which are exposed to a high temperature must be protected against heat and corrosion. This is especially needed for parts of gas turbines like combustions chambers, turbine blades or vanes. These parts are commonly coated with an intermediated MCrAlY-layer and a ceramic thermal barrier coating (TBC) which is applied on top of the intermediate layer.
It is known to use either Gd2Zr207 or Gd2Hf207 as thermal barrier coating.
EP 0 992 603 A1 discloses (Gd, La, Y)2 (Ti, Zr, Hf)2 O7 pyrochlore structures.
EP 1 321 542 A1 discloses an oxide mixture of Gd2O3 and HfO2, wherein Hafnia or gadolinia can be replaced by oxides like Zirconia, Samaria, Europia, Ytterbia or neodynia.