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.

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Thermal barrier coating system

Coated article and method for producing the coated article. The article (1) is coated with a system which provides protection against oxidation and corrosion and which significantly reduces the substrate temperature. An MCrAlY layer (2) is applied to the article (1) to be protected and a columnar grain ceramic (4) is applied by vapor deposition to the MCrAlY coated article. An alumina layer (3) which exists between the MCrAlY layer (2) and the columnar ceramic layer (4) provides for the adherence of the columnar layer to the MCrAlY layer.

Columnar grain ceramic thermal barrier coatings

Coated article and method for producing the coated article. The article (1) is coated with a system which provides protection against oxidation and corrosion and which significantly reduces the substrate temperature. An MCrAlY layer (2) is applied to the article to be protected and a columnar grain ceramic (5) is applied by vapor deposition to the MCrAlY coated article. An alumina layer (4) which exists between the MCrAlY layer (2) and the columnar ceramic layer (5) provides for the adherence of the columnar layer to the MCrAlY layer. An important feature of the invention is that the interface (3) between the MCrAlY layer and the alumina layer has a low surface roughness and this greatly improves the columnar ceramic layer adherence.

Columnar grain ceramic thermal barrier coatings on polished substrates

Adherent, thermal shock-resistant protective coatings for nickel base super alloys are obtained by applying to the base metal a thin bond coat of an alloy of chromium aluminum and yttrium with materials selected from the group consisting of iron, cobalt, nickel and nickel-cobalt and applying thereover a continuously graded mixture of this material with a zirconia-based ceramic, the concentration of zirconia-based ceramic increasing from the bond coat to the outer layer. The zirconia ceramic may be stabilized by the addition thereto of amounts of magnesium oxide or other materials.

Thermal barrier coating for nickel and cobalt base super alloys

A ceramic-coated heat resisting alloy member comprises a base metal (2) mainly composed of at least one of nickel, cobalt and iron; a mixture layer (4) which is deposited on the external surface of the base metal (2) and which comprises a ceramics and a metal; an alloy layer (3) which is formed between the mixture layer (4) and a ceramic coating layer (1) formed as an outermost layer and which comprises an alloy material exhibiting excellent resistance to high temperature oxidation and excellent resistance to high temperature corrosion. It is therefore possible to prevent any high temperature oxidation and high temperature corrosion of the mixture layer (4) and to enable the mixture layer (4) to have a satisfactory function of reducing the thermal stress produced between the ceramic coating layer (1) and the base metal (2). The ceramic coating (1) thus has a satisfactory thermal barrier effect on the base metal (2). In addition, it is therefore possible to provide the ceramic-coated heat resisting alloy member as a useful structural member for improving the power efficiency of gas turbine plants used for power generation.

Ceramics-coated heat resisting alloy member

DESCRIBED IS A PROTECTIVE TREATMENT AS ANTIOXIDANT BARRIER AND AS HEAT BARRIER FOR FERROUS AND NON-FERROUS METALLIC SURFCES. THE TREATMENT COMPRISES SPRAY DEPOSITING IN A MOLTEN STATE A COMBINATION OF POWDERS OF THREE COMPONENTS COMPRISING A METAL ALLOY A, A METAL B, AND A METAL OXIDE C ONTO THE BASE SURFACE.

Process of forming protective coatings on metallic surfaces by spraying a combination of powders of a metal alloy,chromium and a ceramic oxide

Revêtements protecteurs sur matériaux métalliques, ferreux ou non, capables de former écran antioxydant et écran thermique, obtenus par combinaison des poudres d'unalliage métallique, d'un métal et d'un oxyde

Perugini Giancarlo

Papers

Process of forming protective coatings on metallic surfaces by spraying a combination of powders of a metal alloy,chromium and a ceramic oxide

Revêtements protecteurs sur matériaux métalliques, ferreux ou non, capables de former écran antioxydant et écran thermique, obtenus par combinaison des poudres d'unalliage métallique, d'un métal et d'un oxyde

Verfahren zur Herstellung von oxydations- und hitzeresistenten Schutzschichten