Abstract:
A pliable tape is generally provided that includes: a plurality of fibers forming unidirectional arrays of tows encased within a matrix material, with four adjacent fibers in the tape define an interstitial spacing therebetween. The matrix material comprises filler particles dispersed between adjacent fibers in the tape. In one embodiment, the filler particles have a median particle size defining the interstitial spacing such that the interstitial spacing is about 0.75 to about 1.1 of the median particle size. In another embodiment, the filler particles have a median particle size that is related to the surface-to-surface spacing between adjacent fibers, with the ratio of the surface-to-surface spacing between adjacent fibers and the median particle size being about 0.3:1 to about 1:1. Methods are also provided for forming a ceramic matrix composite.
Abstract:
The present application provides methods and apparatus for processing ceramic fibers for the manufacture of ceramic matrix composites (CMCs). One method may include providing at least one frame including a planar array of unidirectional ceramic fibers extending across a void thereof. The method may further include depositing a coating on the ceramic fibers of the at least one frame via a chemical vapor deposition (CVD) process. The method may also include impregnating the coated ceramic fibers with a slurry including a ceramic matrix precursor composition to form at least one CMC prepreg, such as a prepreg tape. The ceramic fibers may be substantially SiC fibers, for example.
Abstract:
The present application provides methods and apparatus for processing ceramic fibers for the manufacture of ceramic matrix composites (CMCs). One method may include providing at least one frame including a planar array of unidirectional ceramic fibers extending across a void thereof. The method may further include at least one of depositing a coating on the ceramic fibers of the at least one frame via a chemical vapor deposition (CVD) process and impregnating the ceramic fibers with a slurry including a ceramic matrix precursor composition to form at least one CMC prepreg. In some embodiments, the ceramic fibers of the planar array may include a coating, and the method may include impregnating the coated ceramic fibers with a slurry including a ceramic matrix precursor composition to form at least one CMC prepreg.
Abstract:
A method can include applying a mask to a CMC structure, and subjecting the structure having an applied mask to a process for repair. In one embodiment, the applying a mask to a CMC structure can include applying a mask to a feature of a CMC structure.
Abstract:
The present application provides methods and apparatus for processing ceramic fibers for the manufacture of ceramic matrix composites (CMCs). One method may include providing at least one frame including a planar array of unidirectional ceramic fibers extending across a void thereof. The method may further include depositing a coating on the ceramic fibers of the at least one frame via a chemical vapor deposition (CVD) process. The method may also include impregnating the coated ceramic fibers with a slurry including a ceramic matrix precursor composition to form at least one CMC prepreg, such as a prepreg tape. The ceramic fibers may be substantially SiC fibers, for example.
Abstract:
Provided is a method including obtaining ceramic matrix composite (CMC) with a first matrix portion including a silicon carbide and silicon phase dispersed therewithin, disposing a coating thereupon to form a sealed part, and forming thereupon another segment comprising a CMC, which may be another matrix portion including a silicon carbide and a silicon phase dispersed within therewithin. Also provided is a gas turbine component with a CMC segment including a matrix portion including a silicon carbide and a silicon phase dispersed therewithin, a sealing layer including silicon carbide enclosing the first segment, and a second segment on the sealing layer, wherein the second segment includes a melt-infiltrated CMC having a matrix portion including a silicon carbide and a silicon phase dispersed therewithin.
Abstract:
A pre-impregnated composite tape is provided that includes: a matrix material; a plurality of fibers forming unidirectional arrays of tows encased within the matrix material; and a plurality of filler particles dispersed between adjacent fibers in the tape. The fibers have a mean fiber diameter of about 5 microns and about 40 microns, and are included within the tape at a volume fraction of about 15% and about 40%. The plurality of filler particles have a log-normal volumetric median particle size, such that the tape has a ratio of the log-normal volumetric median particle size to the mean fiber diameter that is about 0.05:1 to about 1:1. A method is also provided for forming a ceramic matrix composite.
Abstract:
The disclosure relates generally to methods for removing coatings and bond coats of ceramic matrix composites. More specifically, the disclosure relates to, for example, methods of removing a bond coat from a ceramic matrix composite by contacting a ceramic matrix composite with at least one hydroxide at particular temperatures and removing the bond coat from said ceramic matrix composite.