This disclosure enables direct 3D printing of preceramic polymers, which can be converted to fully dense ceramics. Some variations provide a preceramic resin formulation comprising a molecule with two or more CX double bonds or CX triple bonds, wherein X is selected from C, S, N, or O, and wherein the molecule further comprises at least one non-carbon atom selected from Si, B, Al, Ti, Zn, P, Ge, S, N, or O; a photoinitiator; a free-radical inhibitor; and a 3D-printing resolution agent. The disclosed preceramic resin formulations can be 3D-printed using stereolithography into objects with complex shape. The polymeric objects may be directly converted to fully dense ceramics with properties that approach the theoretical maximum strength of the base materials. Low-cost structures are obtained that are lightweight, strong, and stiff, but stable in the presence of a high-temperature oxidizing environment.

This disclosure enables direct 3D printing of preceramic polymers, which can be converted to fully dense ceramics. Some variations provide a preceramic resin formulation comprising a molecule with two or more CX double bonds or CX triple bonds, wherein X is selected from C, S, N, or O, and wherein the molecule further comprises at least one non-carbon atom selected from Si, B, Al, Ti, Zn, P, Ge, S, N, or O; a photoinitiator; a free-radical inhibitor; and a 3D-printing resolution agent. The disclosed preceramic resin formulations can be 3D-printed using stereolithography into objects with complex shape. The polymeric objects may be directly converted to fully dense ceramics with properties that approach the theoretical maximum strength of the base materials. Low-cost structures are obtained that are lightweight, strong, and stiff, but stable in the presence of a high-temperature oxidizing environment.

A ceramic article includes a ceramic matrix composite that has a porous reinforcement structure and a ceramic matrix within pores of the porous reinforcement structure. The ceramic matrix composite includes a surface zone comprised of an exterior surface of the ceramic matrix composite and pores that extend from the exterior surface into the ceramic matrix composite. A glaze material seals the surface zone within the pores of the surface zone and on the exterior surface of the surface zone as an exterior glaze layer on the ceramic matrix composite. The glaze material is a glass or glass-ceramic material. The ceramic matrix composite includes an interior zone under the surface zone, and the interior zone is free of any of the glaze material and has a greater porosity than the surface zone.

A ceramic article includes a ceramic matrix composite that has a porous reinforcement structure and a ceramic matrix within pores of the porous reinforcement structure. The ceramic matrix composite includes a surface zone comprised of an exterior surface of the ceramic matrix composite and pores that extend from the exterior surface into the ceramic matrix composite. A glaze material seals the surface zone within the pores of the surface zone and on the exterior surface of the surface zone as an exterior glaze layer on the ceramic matrix composite. The glaze material is a glass or glass-ceramic material. The ceramic matrix composite includes an interior zone under the surface zone, and the interior zone is free of any of the glaze material and has a greater porosity than the surface zone.

Solid or liquid NH free, C-free, and Si-rich perhydropolysilazane compositions comprising units having the following formula [N(SiH.sub.3).sub.x(SiH.sub.2).sub.y], wherein x=0, 1, or 2 and y=0, 1, or 2 when x+y=2; and x=0, 1 or 2 and y=1, 2, or 3 when x+y=3 are disclosed. Also disclosed are synthesis methods and applications for the same.

Solid or liquid NH free, C-free, and Si-rich perhydropolysilazane compositions comprising units having the following formula [N(SiH.sub.3).sub.x(SiH.sub.2).sub.y], wherein x=0, 1, or 2 and y=0, 1, or 2 when x+y=2; and x=0, 1 or 2 and y=1, 2, or 3 when x+y=3 are disclosed. Also disclosed are synthesis methods and applications for the same.

Resins for 3D printing of a preceramic composition loaded with a solid polymer filler, followed by converting the preceramic composition to a 3D-printed ceramic material, are described. Some variations provide a preceramic composition containing a radiation-curable liquid resin formulation and a solid polymer filler dispersed within the liquid resin formulation. The liquid resin formulation is compatible with stereolithography, UV curing, and/or 3D printing. The solid polymer filler may be an organic polymer, an inorganic polymer, or a combination thereof. The solid polymer filler may itself be an inorganic preceramic polymer, which may have the same composition as a polymerized variant of the liquid resin formulation, or a different composition. Many compositions are disclosed as options for the liquid resin formulation and the solid polymer filler.

Resins for 3D printing of a preceramic composition loaded with a solid polymer filler, followed by converting the preceramic composition to a 3D-printed ceramic material, are described. Some variations provide a preceramic composition containing a radiation-curable liquid resin formulation and a solid polymer filler dispersed within the liquid resin formulation. The liquid resin formulation is compatible with stereolithography, UV curing, and/or 3D printing. The solid polymer filler may be an organic polymer, an inorganic polymer, or a combination thereof. The solid polymer filler may itself be an inorganic preceramic polymer, which may have the same composition as a polymerized variant of the liquid resin formulation, or a different composition. Many compositions are disclosed as options for the liquid resin formulation and the solid polymer filler.

A ceramic article includes a ceramic matrix composite that has a porous reinforcement structure and a ceramic matrix within pores of the porous reinforcement structure. The ceramic matrix composite includes a surface zone and a glaze material within pores of the surface zone and on an exterior side of the surface zone as an exterior glaze layer.

A ceramic article includes a ceramic matrix composite that has a porous reinforcement structure and a ceramic matrix within pores of the porous reinforcement structure. The ceramic matrix composite includes a surface zone and a glaze material within pores of the surface zone and on an exterior side of the surface zone as an exterior glaze layer.