Abstract: Gas turbine engines and related systems involving blade outer air seals are provided. In this regard, a representative blade outer air seal assembly for a gas turbine engine includes: an annular arrangement of outer air seal segments, each of the segments having ends, the segments being positioned in an end-to-end orientation such that each adjacent pair of the segments forms an intersegment gap therebetween, each intersegment gap being defined, at least partially, by a first recess and a first protrusion, the first protrusion being sized and shaped to be received by the first recess, one of the first recess and the first protrusion being located on an end of a first segment of an adjacent pair of the segments, another of the first recess and the first protrusion being located on an end of a second segment of the adjacent pair of the segments.

Abstract: Gas turbine engines and related systems involving blade outer air seals are provided. In this regard, a representative blade outer air seal assembly for a gas turbine engine includes: an annular arrangement of outer air seal segments defining an inner diameter surface; intersegment gaps located between the outer air seal segments, each of the gaps being located between a corresponding adjacent pair of the segments; and recesses spaced about the inner diameter surface, each of the recesses communicating with a corresponding one of the gaps.

Abstract: A component for a gas turbine engine has an airfoil with internal cooling channels for delivering air from a radially outer end of the airfoil toward a radially inner end of the airfoil. The cooling channels are separated from adjacent cooling channels by sets of at least two disconnected wall segments.

Abstract: An article of manufacture has a body formed in part of a first metal alloy and in part of a second metal alloy, the second metal alloy having a thermal coefficient of expansion that is less than the thermal coefficient of expansion of the first metal alloy. A BOAS segment for a gas turbine engine is disclosed wherein the formation of cracks due to thermal mechanical fatigue in the body of the disclosed BOAS segment is minimized, if not eliminated, through a unique construction of the disclosed BOAS segment, whether original equipment manufacture or a repaired blade outer air seal. A method for manufacture of a BOAS segment and a method for modifying a BOAS segment are disclosed.

Abstract: A gas turbine engine article includes a substrate extending between two circumferential sides, a leading edge, a trailing edge, an inner side for resisting hot engine exhaust gases, and an outer side. A gaspath layer is bonded to the inner side of the substrate and includes a metallic alloy having a columnar microstructure.

Abstract: A turbine seal member for use in a gas turbine engine includes a turbine seal substrate having a gas-path side and a ceramic layer disposed on the gas-path side that includes a plurality of mechanical indentations.

Abstract: Systems and methods involving air seals are provided. In this regard, a representative air seal for a gas turbine engine comprises a layer of ceramic exhibiting patterned surface features, wherein a substrate supporting the layer of ceramic lacks the patterned surface features.

Abstract: An outer seal assembly of a turbine rotor stage is secured within a circumferential groove of the turbine casing in such a manner as to both fix the outer seal assembly in its installed position and also provide for sealing around its outer periphery so as to thereby prevent the leakage of cooling air therearound. A plurality of arcuate elements having an angle-shaped cross sectional profile are provided to interface between radially extending arms of the outer seal assembly and the inner surface of the casing, with a locking mechanism then being applied to secure the two structures in their installed positions. Each of the arcuate elements includes a radially extending panel, a plurality of forwardly extending hooks that are disposed within a groove in the casing, and a second forwardly extending flange that engages the rear surface of the outer seal assembly arm.

Abstract: A blade outer air seal for a gas turbine engine is provided. The blade outer air seal includes a body having an outer radial surface, an inner radial surface, and a plurality of cooling air apertures. The body extends between a forward edge and an aft edge. The inner radial surface includes at least one first seal section, at least one second seal section, and a riser extending radially between the first seal section and the second seal section. Each of the plurality of cooling air apertures extends between the outer radial surface and the riser, and each cooling air aperture has an exit configured to direct cooling air substantially parallel to the second seal section of the inner radial surface.

Abstract: A weld set-up and weld process are provided that alleviate micro-cracking as between a pair of welded pieces. The weld set-up is provided in which the weld pieces are configured to cause micro-cracking to occur in a portion of the welded pieces that is then removed by post-processing machining techniques. This weld set-up includes a primary weld piece and a secondary weld piece with a flange portion that extends over the primary weld piece. When used in conjunction with electron beam welding, application of the weld beam onto the secondary weld piece causes the formation of a preferential nailhead that is formed exclusively in the first weld piece.

Abstract: The tip portion of a blade of a gas turbine is repaired in-situ in the gas turbine without removing the blade from the turbine rotor disk. To facilitate the in-situ repair of the tip portion of the turbine blades, one or more access holes may be provided in the turbine shroud or blade outer air seal circumscribing the plurality of turbine blades extending radially outward from the turbine rotor dick.

Abstract: A blade outer air seal (BOAS) casting core has first and second end portions and a plurality of legs. Of these legs, first legs each have: a first end joining the first end portion; a main body portion; and a second end. Second legs each have: a second end joining the second end portion; a main body portion; and a first portion. At least one of the second legs may have its first end joining the core first end portion and a plurality of apertures in the main body portion. Alternatively, at least one of the first legs may have its second end joining the core second end portion and a plurality of apertures in its main body portion.

Abstract: A gas turbine article includes a substrate, a plurality of geometric surface features that protrude from the substrate, and a thermally insulating topcoat disposed over the plurality of geometric surface features. The thermally insulating topcoat includes segmented portions that are separated by faults that extend through the topcoat from the geometric surface features.

Abstract: An outer seal assembly of a turbine rotor stage is secured within a circumferential groove of the turbine casing in such a manner as to both fix the outer seal assembly in its installed position and also provide for sealing around its outer periphery so as to thereby prevent the leakage of cooling air therearound. A plurality of arcuate elements having an angle-shaped cross sectional profile are provided to interface between radially extending arms of the outer seal assembly and the inner surface of the casing, with a locking mechanism then being applied to secure the two structures in their installed positions. Each of the arcuate elements includes a radially extending panel, a plurality of forwardly extending hooks that are disposed within a groove in the casing, and a second forwardly extending flange that engages the rear surface of the outer seal assembly arm.

Abstract: A method of manufacturing a gas turbine engine component includes the steps of forming a ceramic workpiece having oriented ceramic reinforcement, and severing the ceramic workpiece to produce a ceramic member having a desired orientation of the ceramic reinforcement. The ceramic member is then attached to a turbine engine component as a thermal barrier layer for the turbine engine component.

Abstract: An outer seal assembly of a turbine rotor stage is secured within a circumferential groove of the turbine casing in such a manner as to both fix the outer seal assembly in its installed position and also provide for sealing around its outer periphery so as to thereby prevent the leakage of cooling air therearound. A plurality of arcuate elements having an angle-shaped cross sectional profile are provided to interface between radially extending arms of the outer seal assembly and the inner surface of the casing, with a locking mechanism then being applied to secure the two structures in their installed positions. Each of the arcuate elements includes a radially extending panel, a plurality of forwardly extending hooks that are disposed within a groove in the casing, and a second forwardly extending flange that engages the rear surface of the outer seal assembly arm.

Abstract: A blade outer air seal (BOAS) casting core has first and second end portions and a plurality of legs. Of these legs, first legs each have: a proximal end joining the first end portion; a main body portion; and a free distal portion. Second legs each have: a proximal end joining the second end portion; a main body portion; and a free distal portion.

Abstract: A gas turbine engine article includes a substrate extending between two circumferential sides, a leading edge, a trailing edge, an inner side for resisting hot engine exhaust gases, and an outer side. A gaspath layer is bonded to the inner side of the substrate and includes a metallic alloy having a columnar microstructure.

Abstract: An outer seal assembly of a turbine rotor stage is secured within a circumferential groove of the turbine casing in such a manner as to both fix the outer seal assembly in its installed position and also provide for sealing around its outer periphery so as to thereby prevent the leakage of cooling air therearound. A plurality of arcuate elements having an angle-shaped cross sectional profile are provided to interface between radially extending arms of the outer seal assembly and the inner surface of the casing, with a locking mechanism then being applied to secure the two structures in their installed positions. Each of the arcuate elements includes a radially extending panel, a plurality of forwardly extending hooks that are disposed within a groove in the casing, and a second forwardly extending flange that engages the rear surface of the outer seal assembly arm.

Abstract: A material having a plurality of impurity collection spaces has an outer face facing into a cooling air flow stream for a gas turbine engine component. Impurities such as sand or dirt will collect in the plurality of spaces. In a disclosed embodiment, a honeycombed material is utilized. The material may have a surface that will sit with at least a component parallel to an axial centerline of a gas turbine engine that is to receive the collection material. The material surface may also have a component which is generally perpendicular to the axial centerline. The material may be placed in a gas turbine engine upstream of the turbine section, and downstream of the combustion section. Moreover, the collection material may be placed such that there is cleaner air flow radially inwardly of the collection material, and heavier dirt-laden air passing along the collection material such that impurities can be collected.