A gas turbine engine component comprising a nozzle segment, the nozzle segment comprising at least one substrate having a surface. A metallic bondcoat is coupled to the surface of the substrate. An yttria-stabilized zirconia thermal barrier coating is coupled to the metallic bondcoat opposite the surface.

An article such as a heat shield panel includes a substrate and a multi-layered coating supported on the substrate. The multi-layered coating can include alternating layers of different ceramic material compositions having individual thicknesses of less than 25 micrometers.

To provide a Nb-silicide based composite achieving both mechanical characteristics and toughness at high levels in an ultrahigh temperature region (1200 C. or more) as well as a high-temperature component and a high-temperature heat engine which employ the same. The Nb-silicide based composite according to the present invention includes 13 to 23 at % of Si, 2.0 to 10 at % of Cr, 5.0 to 23 at % of Ti, 0.0 to 6.0 at % of Al, 0.10 to 8.0 at % of Zr, 1.0 to 8.0 at % of Hf, 0.0 to 2.0 at % of W, 0.10 to 6.0 at % of Sn, 3.1 to 8.0 at % of Mo, 0.20 to 5.0 at % of B, and the balance being Nb and inevitable impurities.

Novel slurry formulations and processes for forming improved protective coatings used in the hot section components of gas turbine engines are provided. The process includes a unique two-step deposition methodology whereby the required concentration of reactive element within an improved reactive element doped aluminide coating can be consistently produced in a reproducible manner.

A TiAl alloy impeller is composed of a TiAl alloy and is mountable on a vehicle turbocharger. The TiAl alloy has a lamellar structure in which an .sub.2 layer containing Ti.sub.3Al and a layer containing TiAl are alternately stacked. The TiAl alloy impeller includes a shaft portion and blades, each of the blades includes an outer edge, and a region of each of the blades including the outer edge has a processed surface. The processed surface is provided with one or more grooves. At least one of the grooves satisfies a relation of D.sub.g>2R.sub.g or D.sub.g>W.sub.g, where D.sub.g represents a depth of the groove and R.sub.g represents a curvature radius of the groove at a bottom surface of the groove or W.sub.g represents a width of the groove. Thus, a TiAl alloy impeller having high performance as an impeller is provided.

A TiAl alloy impeller is composed of a TiAl alloy and is mountable on a vehicle turbocharger. The TiAl alloy has a lamellar structure in which an .sub.2 layer containing Ti.sub.3Al and a layer containing TiAl are alternately stacked. The TiAl alloy impeller includes a shaft portion and blades, each of the blades includes an outer edge, and a region of each of the blades including the outer edge has a processed surface. The processed surface is provided with one or more grooves. At least one of the grooves satisfies a relation of D.sub.g>2R.sub.g or D.sub.g>W.sub.g, where D.sub.g represents a depth of the groove and R.sub.g represents a curvature radius of the groove at a bottom surface of the groove or W.sub.g represents a width of the groove. Thus, a TiAl alloy impeller having high performance as an impeller is provided.