Abstract: A method for forming a ceramic matrix composite (CMC) component for gas turbine engines. The method contemplates replacing a plurality of plies with insert material. The insert material can be partially cured or pre-cured and applied in place of a plurality of small plies or it may be inserted into cavities of a component in the form of a paste or a ply. The insert material is isotropic, being formed of a combination of matrix material and chopped fibers, tow, cut plies or combinations thereof. The use of the insert material allows for features such as thin edges with thicknesses of less than about 0.030 inches and small radii such as found in corners. The CMC components of the present invention replace small ply inserts cut to size to fit into areas of contour change or thickness change, and replace the small ply inserts with a fabricated single piece discontinuously reinforced composite insert, resulting in fewer defects, such as wrinkles, and better dimensional control.

Abstract: A method of manufacturing a turbine engine component comprising the steps of providing and laying up a plurality of ceramic plies comprising woven ceramic fiber tows to form a turbine engine component shape, inserting a plurality of tows of oxidizable fugitive fibers into the component shape, such that each fugitive fiber tow passes through a preselected number of ceramic plies, burning off the fugitive fiber tows, the burning producing through-thickness void regions, rigidizing the component shape with a layer of BN and a layer of SiC to form a coated component preform using chemical vapor infiltration, and partially densifying the coated component preform using carbon-containing slurry and filling the through thickness void regions, and further densifying the coated component preform with at least silicon to form a ceramic matrix composite turbine engine component with in-situ ceramic matrix plugs formed where the through-thickness void regions were located.

Abstract: The integral layer provides a ductile interface for attachment locations of a turbine engine component where a metallic surface is adjacent the attachment location. The ductile layer provides a favorable load distribution through the composite at the attachment location, and eliminates the need for a metallic shim.

Abstract: A preform architecture and process for producing composite materials, and particularly CMC components. The process entails producing a composite component having a matrix material reinforced with a three-dimensional preform. The process includes producing first and second sets of tows containing filaments. Each tow of the first set has a predetermined cross-sectional shape and is embedded within a temporary matrix material formed of a material that is not the matrix material or a precursor of the matrix material. The preform is then fabricated from the first and second sets of tows, in which the second set of tows are transverse to the first set of tows, adjacent tows of the second set are spaced apart to define interstitial regions therebetween, and the cross-sectional shapes of the first set of tows are substantially congruent to the cross-sectional shapes of the interstitial regions so as to substantially fill the interstitial regions.

Abstract: A ceramic matrix composite (CMC) component for gas turbine engines, the component having fine features such as thin edges with thicknesses of less than about 0.030 inches and small radii of less that about 0.030 inches formed using the combination of prepreg plies layed up with non-ply ceramic inserts. The CMC components of the present invention replace small ply inserts cut to size to fit into areas of contour change or thickness change, and replace the small ply inserts with a fabricated single piece discontinuously reinforced composite insert, resulting in fewer defects, such as wrinkles, and better dimensional control.

Abstract: The integral layer provides a ductile interface for attachment locations of a turbine engine component where a metallic surface is adjacent the attachment location. The ductile layer provides a favorable load distribution through the composite at the attachment location, and eliminates the need for a metallic shim.

Abstract: A method for making a ceramic matrix composite turbine engine component, wherein the method includes providing a plurality of biased ceramic plies, wherein each biased ply comprises ceramic fiber tows, the tows being woven in a first warp direction and a second weft direction, the second weft direction lying at a preselected angular orientation with respect to the first warp direction, wherein a greater number of tows are woven in the first warp direction than in the second weft direction. The plurality of biased plies are laid up in a preselected arrangement to form the component, and a preselected number of the plurality of biased plies are oriented such that the orientation of the first warp direction of the plies lie about in the direction of maximum tensile stress during normal engine operation. A coating is applied to the plurality of biased plies. The coated component preform is then densified.

Abstract: An orthogonal stitch-weave method and fiber architecture. The architecture allows near-net-shape composite preforms to be fabricated, thereby reducing costs associated with complex preform shapes and increasing desired strengths of the composite.

Abstract: The present invention is a ceramic matrix composite turbine engine component, wherein the component has a region of expected higher interlaminate stress during normal engine operation. The component includes both coated fiber tows and uncoated fiber tows arranged together into a preselected form, wherein the uncoated fiber tows are located at predetermined regions of expected high interlaminate stress. The invention further includes method of manufacturing a CMC such as a composite turbine engine component, wherein the component has a region of expected higher interlaminate stress during engine operation.

Abstract: A bond coat composition is provided for applying to the surface of a ceramic composite component between the composite substrate and the thermal barrier coat. The composition includes an alumina powder, a silica-yielding liquid, glass frits, and sufficient solvent to permit mixing of the components and forming a bond coat.

Abstract: A fiber reinforced composite article, comprising a matrix and reinforcing fibers and subjected during operation concurrently to a plurality of temperatures and stresses, varying between a plurality of regions of the article, experiences different stresses concurrently in different regions of the article. The article is provided with fiber reinforcement of a strength in each region greater than the stress experienced in that region. Such fiber reinforcement is provided through a member for inclusion in the matrix, for example in the form of at least one of a fabric, weave, braid, lay-up, etc. One form of such an article for use at relatively high temperatures is a turbine engine component, for example a gas turbine engine exhaust flap. Another form of such an article is a gas turbine engine blading component.

Abstract: A fiber reinforced composite article comprising a matrix and reinforcing fibers, and different operating temperature and stress combinations each across opposed surfaces and through the matrix, is made by first measuring each of the combinations. Then discrete regions, each extending completely through the surfaces and the matrix, are selected for each combination. Reinforcing fibers with strength greater than the stress in a selected region are disposed in each selected region, the strengths being different between regions responsive to the different measured combinations.

Abstract: A fiber reinforced composite article, comprising a matrix and reinforcing fibers and subjected during operation concurrently to a plurality of temperatures and stresses, varying between a plurality of regions of the article, experiences different stresses concurrently in different regions of the article. The article is provided with fiber reinforcement of a strength in each region greater than the stress experienced in that region. Such fiber reinforcement is provided through a member for inclusion in the matrix, for example in the form of at least one of a fabric, weave, braid, lay-up, etc. One form of such an article for use at relatively high temperatures is a turbine engine component, for example a gas turbine engine exhaust flap. Another form of such an article is a gas turbine engine blading component.