Patent ID: 10730203

Abstract:
A method of making a ceramic matrix composite (CMC) article by combining a preceramic polymer with one or more sized nanopowders and optional surfactants and/or solvents to form a mixture suitable for 3D printing, depositing the mixture on a mandrel, curing it to form a green body, and pyrolyzing the green body such that the nanocrystalline surface of the CMC article has sufficiently the same surface roughness and figure accuracy of the mandrel to enable the CMC article to be used without further polishing. The mixture can be a paste or slurry that is self supporting and exhibit pseudoplastic rheology. The preceramic polymer is preferably a precursor to SiC, and the nanopowders preferably comprise SiC. The article can be densified by using polymer infiltration pyrolysis, with or without nanoparticles. The curing and pyrolysis of the article can be performed with microwave radiation. An example structure is a gradient density lattice with a mirror surface for use in a cryogenically cooled infrared optical system such as an orbiting space telescope.