Abstract: A heat shield which is adapted to be formed on an article which must operate in an environment in which the article is subject to thermal radiation while at an elevated service temperature. The heat shield is composed of a barrier layer formed or deposited on the surface of the article, and a reflective layer on the barrier layer. The reflective layer serves to reflect a majority of the thermal radiation which is incident on the article. The barrier layer serves to substantially prevent degradation of the reflective layer at the elevated service temperature, so as to prevent the reflectivity of the reflective layer from being degraded while the article is in service. The reflective layer is preferably a noble metal, a noble metal alloy or aluminum, while the barrier layer is preferably a nitride, aluminum oxide, yttria-stabilized zirconia, or an oxide which can be grown by oxidation of the article's surface.

Abstract: A heat shield which is adapted to be formed on an article which must operate in an environment in which the article is subject to thermal radiation while at an elevated service temperature. The heat shield is composed of a barrier layer formed or deposited on the surface of the article, and a reflective layer on the barrier layer. The reflective layer serves to reflect a majority of the thermal radiation which is incident on the article. The barrier layer serves to substantially prevent degradation of the reflective layer at the elevated service temperature, so as to prevent the reflectivity of the reflective layer from being degraded while the article is in service. The reflective layer is preferably a noble metal, a noble metal alloy or aluminum, while the barrier layer is preferably a nitride, aluminum oxide, yttria-stabilized zirconia, or an oxide which can be grown by oxidation of the article's surface.

Abstract: A catalyst-bearing component of a gas turbine engine is provided. Catalytic materials are provided on components defining the gas flow path of the engine, so that emissions of carbon monoxide and unburned hydrocarbons are reduced. The catalytic materials are selected from the group consisting of noble metals and transition metal oxides. The portions of the gas flow path where such materials are advantageously applied include the combustor, the turbine and the exhaust system. The catalytic coating is preferably applied in conjunction with a thermal barrier coating system interposed between a substrate component and the catalytic coating.