A blade includes an airfoil section extending between leading and trailing edges, first and second opposed sides each joining the leading and trailing edges, and an inner end and a free end. The blade also includes an abrasive tip at the free end of the airfoil section. The abrasive tip includes particles diposed in a matrix material. The matrix material is a polymeric material that has a glass transition temperature greater than or equal to about 225 degrees C. (487 degrees F.). A gas turbine engine and a method of fabricating a blade are also disclosed.

An investment casting process for manufacturing a cast component is provided. The investment casting process includes forming a core, casting the cast component about the core such that a core positioning feature provides a location of an anticipated pilot hole in the cast component, removing the core from the cast component once the casting is completed, locating, forming and sizing a pilot hole to form a resized pilot hole that can receive a sealing plug and installing the sealing plug into the resized pilot hole.

A shroud configured to be disposed around an impeller of a centrifugal compressor, the shroud has a wall extending circumferentially around a central axis, the wall having an inner face oriented toward a gaspath and an outer face opposed to the inner face, a bleed slot defined in the wall and extending along at least a portion of a circumference thereof, the bleed slot defining a bleed direction from the inner face and away from the gaspath, the bleed direction at the inner face of the wall being either parallel to the central axis or oriented toward the central axis. A method of manufacturing a shroud is provided.

A shroud configured to be disposed around an impeller of a centrifugal compressor, the shroud has a wall extending circumferentially around a central axis, the wall having an inner face oriented toward a gaspath and an outer face opposed to the inner face, a bleed slot defined in the wall and extending along at least a portion of a circumference thereof, the bleed slot defining a bleed direction from the inner face and away from the gaspath, the bleed direction at the inner face of the wall being either parallel to the central axis or oriented toward the central axis. A method of manufacturing a shroud is provided.

An apparatus and method regarding forming a cooling hole in a component for a turbine engine, with the component held in a hole-forming machine with a laser carried on a multi-axis carriage and defining an optical path, the method comprising forming a set of cooling holes in the component with a laser mounted to the multi-axis carriage, estimating a total airflow through the set of cooling holes based on a set of data regarding the flow effectiveness of the set of cooling holes, and forming a second set of cooling holes with the laser.

An apparatus and method regarding forming a cooling hole in a component for a turbine engine, with the component held in a hole-forming machine with a laser carried on a multi-axis carriage and defining an optical path, the method comprising forming a set of cooling holes in the component with a laser mounted to the multi-axis carriage, estimating a total airflow through the set of cooling holes based on a set of data regarding the flow effectiveness of the set of cooling holes, and forming a second set of cooling holes with the laser.

Methods for manufacturing a tandem guide vane segment that includes an outer platform, a front guide vane, and a rear guide vane, wherein the front guide vane and the rear guide vane are arranged in a firmly fixated manner with respect to one another. One method includes manufacturing an integral front segment section that includes the front guide vane and a front section of the outer platform, manufacturing an integral rear segment section that includes the rear guide vane and a rear section of the outer platform, and connecting the two segment sections to each other.

Methods for manufacturing a tandem guide vane segment that includes an outer platform, a front guide vane, and a rear guide vane, wherein the front guide vane and the rear guide vane are arranged in a firmly fixated manner with respect to one another. One method includes manufacturing an integral front segment section that includes the front guide vane and a front section of the outer platform, manufacturing an integral rear segment section that includes the rear guide vane and a rear section of the outer platform, and connecting the two segment sections to each other.

An assembly for a dual-walled component of a gas turbine engine and methods of forming and repairing a dual-walled component. The assembly includes a cold section part having an outer surface that defines a plurality of impingement apertures, a hot section part including a pre-sintered preform, the hot section part positioned over the outer surface of the cold section part, and a plurality of support structures including the pre-sintered preform, the plurality of support structures positioned between the hot section part and the cold section part, the plurality of support structures separating the hot section part from the cold section part to define at least one cooling channel therebetween.

An assembly for a dual-walled component of a gas turbine engine and methods of forming and repairing a dual-walled component. The assembly includes a cold section part having an outer surface that defines a plurality of impingement apertures, a hot section part including a pre-sintered preform, the hot section part positioned over the outer surface of the cold section part, and a plurality of support structures including the pre-sintered preform, the plurality of support structures positioned between the hot section part and the cold section part, the plurality of support structures separating the hot section part from the cold section part to define at least one cooling channel therebetween.