The present invention provides a TiAl-based alloy, including: Al: 41 to 43 at %; Fe: 0 to 2.5 at %; Ni: 0 to 2.5 at %; Mo: 0 to 2.0 at %; W: 0 to 2.0 at %; Cr: 0 to 4.5 at %; Mn: 0 to 5.5 at %; V: 0 to 10 at %; Nb: 0 to 10 at %; C: 0.3 to 0.7 at %; and a remainder consisting of Ti and inevitable impurities, in which an alloy element parameter “P=(41.5−Al)/3+Fe+Ni+Mo+W+0.5 Cr+0.4 Mn+0.2 V+0.2 Nb—C” is in a composition range of 1.1 to 1.9, and the TiAl-based alloy has a microstructure consisting of a γ phase of 5 to 30 area %, a β phase of 0.5 to 5 area %, and a lamellar structure occupying a remaining part.

A gas turbine engine component having a substrate; a thermal barrier coating on the substrate having a porous microstructure; and a reflective layer conforming to the porous microstructure of the thermal barrier coating, wherein the reflective layer comprises a conforming nanolaminate defined by alternating layers of platinum group metal materials selected from the group consisting of platinum group metal-based alloys, platinum group metal intermetallic compounds, mixtures of platinum group metal with metal oxides and combinations thereof. A capping layer can be added over the reflective layer. A supporting layer can be added between the reflective layer and the thermal barrier coating. A process is also disclosed.

A coated substrate has a substrate and a coating system having one or more ceramic layers. At least a first layer of one of the one or more ceramic layers is a columnar layer having as-deposited columns and intercolumn gaps. The intercolumn gaps have a mean width at least one of: at least 4.0 micrometers; and at least 1.5% of a thickness of said first layer.

An airfoil includes an airfoil section that has an airfoil wall that defines an arced leading end, a trailing end, and first and second sides that join the arced leading end and the trailing end. The first and second sides span in a longitudinal direction between first and second ends. The airfoil wall circumscribes an internal core cavity. There is an arced rib in the internal core cavity. A cooling passage network is embedded in the airfoil wall between inner and outer portions of the airfoil wall. The cooling passage network has a trailing edge and an arced leading edge.

A coated substrate has a substrate and a coating system having one or more ceramic layers. At least a first layer of one of the one or more ceramic layers is a columnar layer having as-deposited columns and intercolumn gaps. The intercolumn gaps have a mean width at least one of: at least 4.0 micrometers; and at least 1.5% of a thickness of said first layer.

A process for coating a component includes applying a bond coat on a substrate of a component; applying a thermal barrier material to the bond coat; and applying a conforming reflective layer to the thermal barrier material, the conforming reflective layer conforming to porous microstructure of the ceramic coating.

A method of treating a component for a gas turbine engine according to an example of the present disclosure includes, among other things, injecting a suspension stream into a plasma gas stream, the suspension stream having coating particles moving in the gas stream toward a component, and placing the coating particles on the component at a coating location to form a top coat that has a columnar microstructure such that a porosity of the columnar microstructure is between 4.0-7.0 percent, exclusive of the intersegment gaps.

A unidirectionally solidified article repair method according to one embodiment includes a step of forming a groove part overlapping only on one of a plurality of crystal grain boundaries in a base material made of a unidirectionally solidified alloy in which the plurality of crystal grain boundaries are aligned in one direction, and a step of forming a welded part having a metal composition similar to that of the base material by a metal used in welding with the base material in the groove part.

CMC components having microchannels and methods for forming microchannels in CMC components are provided. For example, a method for forming microchannels in a CMC component comprises laying up a plurality of body plies for forming a body of the CMC component; laying up a microchannel ply on the plurality of body plies that has at least one void therein for forming at least one microchannel; laying up a cover ply on the microchannel ply to define an outer layer of the CMC component; and processing the laid up body plies, microchannel ply, and cover ply to form the CMC component. In another embodiment, the method comprises applying an additive matrix to the body plies to define at least one microchannel. In still other embodiments, the method comprises machining at least one microchannel in the plurality of body plies.

In one aspect, a calcium-magnesium alumino-silicate (CMAS)-resistant coating includes an outer coating having a plurality of columnar structures formed during material deposition due to preferential material accumulation and a plurality of generally vertically-oriented gaps separating adjacent columnar structures. The columnar structures include a plurality of randomly-oriented particle splats and a CMAS-reactive material and have a total porosity of less than five percent. The plurality of generally vertically-oriented gaps extend from an outermost surface of the outer coating to a first depth of the outer coating equal to or less than a total thickness of the outer coating. The vertically-oriented gaps have a median gap width of less than five micrometers.