Abstract: Systems and methods for infiltrating porous ceramic matrix composite (CMC) preforms to form CMC articles are disclosed. One method may include positioning the porous CMC preform in an opening of a die set for an infiltration system, and flowing a molten densifier over the porous CMC preform in a first flow direction to infiltrate a plurality of voids formed between each of a plurality of ply stacks of the CMC preform. The method may also include flowing the molten densifier over the porous CMC preform in a second flow direction, distinct from the first flow direction, to infiltrate the plurality of voids formed between each of the plurality of ply stacks of the CMC preform. The second flow direction may be substantially parallel to a predetermined, unidirectional material orientation of at least one ply stack of the plurality of ply stacks of the CMC preform.

Abstract: A ceramic matrix composite (CMC) component includes at least one seal surface, the at least one seal surface disposed adjacent an interfacing surface for providing a seal therebetween; and a coating disposed on the seal surface. The coating includes an aluminum oxide and/or a silicon dioxide.

Abstract: An apparatus is disclosed, including a first article, a second article, at least one interface structure, and a thermal break directly adjacent to the at least one interface structure. The first article includes a first material composition having a first thermal tolerance. The second article includes a second material composition having a second thermal tolerance greater than the first thermal tolerance. The first article and the second article are in contact with one another through the interface structure. The thermal break interrupts a thermal conduction path from the second article to the first article.

Abstract: Various embodiments include methods for densifying a melt infiltrated ceramic matrix composite (CMC) article, and a densified melt infiltrated CMC article formed thereby. Particular embodiments include a method including: providing a porous CMC preform within a first region of a casting apparatus; providing a molten densifier within a pressure head area of a second region of the casting apparatus, the first and second regions being operably connected and the molten densifier including at least one source of silicon; and applying a first pressure to the molten densifier within the pressure head, thereby infiltrating voids within the porous CMC preform with the molten densifier and forming a densified melt infiltrated CMC article.

Abstract: Methods for preparing ceramic matrix composites using melt infiltration and chemical vapor infiltration are provided as well as the resulting ceramic matrix composites. The methods and products include the incorporation of sacrificial fibers to provide improved infiltration of the fluid infiltrant. The sacrificial fibers are removed, such as decomposed during pyrolysis, resulting in the formation of regular and elongate channels throughout the ceramic matrix composite. Infiltration of the fluid infiltrant can then take place using the elongate channels resulting in improved density and an improved ceramic matrix composite product.

Abstract: A coating includes: at least 34.9 percent by mass silicon dioxide; at least 9.1 percent by mass aluminum oxide; and at least 16.1 percent by mass yttrium oxide.

Abstract: Systems and methods for infiltrating porous ceramic matrix composite (CMC) preforms to form CMC articles are disclosed. One method may include positioning the porous CMC preform in an opening of a die set for an infiltration system, and flowing a molten densifier over the porous CMC preform in a first flow direction to infiltrate a plurality of voids formed between each of a plurality of ply stacks of the CMC preform. The method may also include flowing the molten densifier over the porous CMC preform in a second flow direction, distinct from the first flow direction, to infiltrate the plurality of voids formed between each of the plurality of ply stacks of the CMC preform. The second flow direction may be substantially parallel to a predetermined, unidirectional material orientation of at least one ply stack of the plurality of ply stacks of the CMC preform.

Abstract: Various embodiments include methods for densifying a melt infiltrated ceramic matrix composite (CMC) article, and a densified melt infiltrated CMC article formed thereby. Particular embodiments include a method including: providing a porous CMC preform within a first region of a casting apparatus; providing a molten densifier within a pressure head area of a second region of the casting apparatus, the first and second regions being operably connected and the molten densifier including at least one source of silicon; and applying a first pressure to the molten densifier within the pressure head, thereby infiltrating voids within the porous CMC preform with the molten densifier and forming a densified melt infiltrated CMC article.

Abstract: A coating includes: at least 34.9 percent by mass silicon dioxide; at least 9.1 percent by mass aluminum oxide; and at least 16.1 percent by mass yttrium oxide.

Abstract: A ceramic matrix composite (CMC) component includes at least one seal surface, the at least one seal surface disposed adjacent an interfacing surface for providing a seal therebetween; and a coating disposed on the seal surface. The coating includes an aluminum oxide and/or a silicon dioxide.

Abstract: The present disclosure is directed to a method for forming a passage in a composite component. The method includes forming a cavity in a fiber preform. The cavity forms a portion of the passage. The method also includes inserting a core into the cavity and placing one or more fiber plies onto the fiber preform to form a fiber preform assembly. The method further includes thermally processing the fiber preform assembly and densifying the fiber preform assembly to form the composite component. The method also includes removing the core from the composite component.

Abstract: Methods for preparing ceramic matrix composites using melt infiltration and chemical vapor infiltration are provided as well as the resulting ceramic matrix composites. The methods and products include the incorporation of sacrificial fibers to provide improved infiltration of the fluid infiltrant. The sacrificial fibers are removed, such as decomposed during pyrolysis, resulting in the formation of regular and elongate channels throughout the ceramic matrix composite. Infiltration of the fluid infiltrant can then take place using the elongate channels resulting in improved density and an improved ceramic matrix composite product.

Abstract: A method of forming a pre-form ceramic matrix composite mold for a ceramic matrix composite (CMC) component including providing pieces of CMC remnant scrap material and randomly arranging the pieces of CMC remnant scrap material relative to one another. The method further includes debulking the pieces of CMC remnant scrap material into a rigidized shape, the rigidized shape having gaps between adjacent pieces of CMC remnant scrap material of about 10 microns and about 10 mm and a gap spacing between about 50 microns and about 50 mm, and forming the rigidized shape into a mold.

Abstract: Methods for preparing ceramic matrix composites using melt infiltration and chemical vapor infiltration are provided as well as the resulting ceramic matrix composites. The methods and products include the incorporation of sacrificial fibers to provide improved infiltration of the fluid infiltrant. The sacrificial fibers are removed, such as decomposed during pyrolysis, resulting in the formation of regular and elongate channels throughout the ceramic matrix composite. Infiltration of the fluid infiltrant can then take place using the elongate channels resulting in improved density and an improved ceramic matrix composite product.

Abstract: Methods for preparing ceramic matrix composites using melt infiltration and chemical vapor infiltration are provided as well as the resulting ceramic matrix composites. The methods and products include the incorporation of sacrificial fibers to provide improved infiltration of the fluid infiltrant. The sacrificial fibers are removed, such as decomposed during pyrolysis, resulting in the formation of regular and elongate channels throughout the ceramic matrix composite. Infiltration of the fluid infiltrant can then take place using the elongate channels resulting in improved density and an improved ceramic matrix composite product.

Abstract: A method of treating a ceramic matrix composite article, including selecting an article having a ceramic composition formed by a process comprising an initial melt infiltration at an initial temperature with an initial infiltration material, whereby said article has at least one treatable feature. A portion of the ceramic composite is removed from a region abutting the treatable feature to form a treatment region. A treatment material including a reinforcing fiber is positioned in the treatment region and densified by a first melt infiltration with a first infiltration material including silicon. The first melt infiltration is performed at a first temperature lower than the initial infiltration temperature of the initial melt infiltration.

Abstract: A method of making a preform and preform formed by the method. The method includes providing a first pre-preg ply including at least a first fiber and a first resin. The method also includes providing a second pre-preg ply including at least a second fiber and a second resin over at least a portion of the first pre-preg ply. Heat or electromagnetic radiation is used to at least partially cure the first and second resins to form a cured preform. Heat is applied to pyrolyze at least a portion of the resin of the cured preform to form a pyrolyzed preform. A mechanical stimulus including at least one of controlled drying, local explosions, or ultrasonic energy is applied to the pyrolyzed preform. The mechanically treated pyrolyzed preform is subsequently densified by melt infiltration to form a densified preform.

Abstract: The present disclosure is directed to a method for forming a passage in a composite component. The method includes forming a cavity in a fiber preform. The cavity forms a portion of the passage. The method also includes inserting a core into the cavity and placing one or more fiber plies onto the fiber preform to form a fiber preform assembly. The method further includes thermally processing the fiber preform assembly and densifying the fiber preform assembly to form the composite component. The method also includes removing the core from the composite component.

Abstract: A method of forming a pre-form ceramic matrix composite mold for a ceramic matrix composite (CMC) component including providing pieces of CMC remnant scrap material and randomly arranging the pieces of CMC remnant scrap material relative to one another. The method further includes debulking the pieces of CMC remnant scrap material into a rigidized shape, the rigidized shape having gaps between adjacent pieces of CMC remnant scrap material of about 10 microns and about 10 mm and a gap spacing between about 50 microns and about 50 mm, and forming the rigidized shape into a mold.

Abstract: An apparatus is disclosed, including a first article, a second article, at least one interface structure, and a thermal break directly adjacent to the at least one interface structure. The first article includes a first material composition having a first thermal tolerance. The second article includes a second material composition having a second thermal tolerance greater than the first thermal tolerance. The first article and the second article are in contact with one another through the interface structure. The thermal break interrupts a thermal conduction path from the second article to the first article.