More commonly, non-traditional high temperature composite materials, such as ceramic matrix composite (CMC) and polymer matrix composite (PMC) materials, are being used in applications such as gas turbine engines. Components fabricated from such materials have a higher temperature capability compared with typical components, e.g., metal components, which may allow improved component performance and/or increased engine temperatures. Composite components may provide other advantages as well, such as an improved strength to weight ratio.
Often, composite components are formed at least in part from a plurality of plies of the composite material. The composite plies may be cut from a tape or sheet of a composite matrix, which also may comprise other constituents such as solvents and binders, and then stacked to form a composite ply layup. Typically, stacks of plies have irregular finished edges and the plies may move relative to one another as the ply stack is processed to form the composite component. The irregular finished edges as well as the relative motion between the plies may leave gaps in an assembly of composite ply sub-assemblies, such as an assembly of composite ply layups, composite plies, composite ply packs, etc. Such gaps may require a filler material and/or additional densification material to reduced or eliminate the gaps, which may increase manufacturing complexity, time, and/or cost of composite components. Further, such gaps may reduce the integrity of the composite component, which may decrease part yield and increase part scrap rate, as well as decrease time on wing and unplanned service calls for repairs.
Accordingly, improved composite components and methods for forming composite components would be useful. In particular, methods for forming composite components that yield composite ply assemblies with fewer or no gaps between composite plies and/or composite ply sub-assemblies would be beneficial. As an example, methods for green machining a composite ply layup to shape one or more surfaces or edges of the layup for a better fit with an adjacent composite ply sub-assembly would be advantageous.
USPTO Backgrounds
USPTO Backgrounds