Abstract: An oxide thermal barrier coating comprises ZrO.sub.3 --Yb.sub.2 O.sub.3 that is plasma sprayed onto a previously applied bond coating. The zirconia is partially stabilized with about 12.4 w/o ytterbia to insure cubic, monoclinic, and tetragonal phases.

Abstract: This invention relates to a high temperature oxidation resistant thermal barrier coating system for a nickel-, cobalt-, or iron-base alloy substrate. An inner metal bond coating contacts the substrate, and a thermal barrier coating covers the bond coating.NiCrAlR, FeCrAlR, and CoCrAlR alloys have been satisfactory as bond coating compositions where R=Y or Yb. These alloys contain, by weight, 24.9-36.7% chromium, 5.4-18.5% aluminum, and 0.05 to 1.55% yttrium or 0.05 to 0.53% ytterbium. The coatings containing ytterbium are preferred over those containing yttrium.An outer thermal barrier coating of partially stabilized zirconium oxide (zirconia) which is between 6% and 8%, by weight, of yttrium oxide (yttria) covers the bond coating. Partial stabilization provides a material with superior durability. Partially stabilized zirconia consists of mixtures of cubic, tetragonal, and monoclinic phases.

Abstract: A coating system which contains a bond coating and a thermal barrier coating is applied to metal surfaces such as turbine blades and which provides both low thermal conductivity and improved adherence when exposed to high temperature gases or liquids. The bond coating contains NiCrAlY and the thermal barrier coating contains a reflective oxide. The reflective oxides ZrO.sub.2 --Y.sub.2 O.sub.3 and ZrO.sub.2 --MgO have demonstrated significant utility in high temperature turbine applications.