Ceramic matrix composite articles include, for example, a plurality of unidirectional arrays of fiber tows in a matrix having a monomodal pore size distribution, and a fiber volume fraction between about 15 percent and about 35 percent. The articles may be formed by, for example, providing a shaped preform comprising a prepreg tape layup of unidirectional arrays of fiber tows, a matrix precursor, and a pore former, curing the shaped preform to pyrolyze the matrix precursor and burnout the pore former so that the shaped preform comprises the unidirectional arrays of fiber tows and a porous matrix having a monomodal pore size distribution, and subjecting the cured shaped preform to chemical vapor infiltration to densify the porous matrix so that the ceramic matrix composite article has a fiber volume fraction between about 15 percent and about 35 percent.

A method of producing a ceramic matrix composite component. The method includes positioning a first plurality of ceramic matrix composite plies on top of one another, disposing a filler pack on the first plurality of ceramic matrix composite plies, and positioning a second plurality of ceramic matrix composite plies on top of the filler pack. One of the first plurality of ceramic composite plies or the second plurality of ceramic composite plies includes a bend angle, to define an interstice between the plurality of ceramic matrix composite plies with the filler pack disposed in the interstice. The filler pack includes one or more sacrificial fibers disposed therein, that subsequent to removal provide a functional feature, such as a cooling manifold in the filler pack. The method further includes forming one or more channels coupled to the one or more functional features for the flow of a cooling fluid therethrough. A ceramic matrix composite is also disclosed.

A method of manufacturing a ceramic matrix composite (CMC) turbine nozzle shell is provided. The method includes: assembling a primary outer nozzle platform, a primary inner nozzle platform, a core and trailing edge preform, and an airfoil-shaped body; joining the primary outer nozzle platform to a secondary outer nozzle platform of the airfoil-shaped body; and joining the primary inner nozzle platform to a secondary inner nozzle platform of the airfoil-shaped body. Composite plies circumferentially surround the airfoil-shaped body, and their longitudinal edges are cut into fingers that are folded down. The fingers are interleaved between secondary platform plies to form the secondary outer and inner nozzle platforms.

Dry prepregs for ceramic matrix composites are described. The dry prepregs comprise a tow or fabric of ceramic fibers infiltrated with preceramic matrix comprising low levels of an aqueous solvent. The preceramic matrix contains an inorganic portion and a binder system. Binder systems comprising a binder and a plasticizer for the binder are described.

A method of producing a ceramic matrix composite component. The method includes positioning a first plurality of ceramic matrix composite plies on top of one another, disposing a filler pack on the first plurality of ceramic matrix composite plies, and positioning a second plurality of ceramic matrix composite plies on top of the filler pack. One of the first plurality of ceramic composite plies or the second plurality of ceramic composite plies includes a bend angle, to define an interstice between the plurality of ceramic matrix composite plies with the filler pack disposed in the interstice. The filler pack includes one or more sacrificial fibers disposed therein, that subsequent to removal provide a functional feature, such as a cooling manifold in the filler pack. The method further includes forming one or more channels coupled to the one or more functional features for the flow of a cooling fluid therethrough. A ceramic matrix composite is also disclosed.

Waste flax straw from the harvesting of flaxseeds from flax plants is processed to produce a flax straw substrate. The flax straw substrate includes a mixture of flax fibers and flax shives. A binding agent is mixed with the flax straw substrate to produce a wet flax straw substrate mixture. The wet flax straw substrate mixture is deposited into a form. Heat and pressure are applied to the form to cure the binding agent, creating a flax straw based building material.

A method of manufacturing a ceramic matrix composite (CMC) turbine nozzle shell is provided. The method includes: assembling a primary outer nozzle platform, a primary inner nozzle platform, a core and trailing edge preform, and an airfoil-shaped body; joining the primary outer nozzle platform to a secondary outer nozzle platform of the airfoil-shaped body; and joining the primary inner nozzle platform to a secondary inner nozzle platform of the airfoil-shaped body. Composite plies circumferentially surround the airfoil-shaped body, and their longitudinal edges are cut into fingers that are folded down. The fingers are interleaved between secondary platform plies to form the secondary outer and inner nozzle platforms.

Ceramic matrix composite articles include, for example, a plurality of unidirectional arrays of fiber tows in a matrix having a monomodal pore size distribution, and a fiber volume fraction between about 15 percent and about 35 percent. The articles may be formed by, for example, providing a shaped preform comprising a prepreg tape layup of unidirectional arrays of fiber tows, a matrix precursor, and a pore former, curing the shaped preform to pyrolyze the matrix precursor and burnout the pore former so that the shaped preform comprises the unidirectional arrays of fiber tows and a porous matrix having a monomodal pore size distribution, and subjecting the cured shaped preform to chemical vapor infiltration to densify the porous matrix so that the ceramic matrix composite article has a fiber volume fraction between about 15 percent and about 35 percent.

Waste flax straw from the harvesting of flaxseeds from flax plants is processed to produce a flax straw substrate. The flax straw substrate includes a mixture of flax fibers and flax shives. A binding agent is mixed with the flax straw substrate to produce a wet flax straw substrate mixture. The wet flax straw substrate mixture is deposited into a form. Heat and pressure are applied to the form to cure the binding agent, creating a flax straw based building material.

Dry prepregs for ceramic matrix composites are described. The dry prepregs comprise a tow or fabric of ceramic fibers infiltrated with preceramic matrix comprising low levels of an aqueous solvent. The preceramic matrix contains an inorganic portion and a binder system. Binder systems comprising a binder and a plasticizer for the binder are described.