C04B35/589

Resin formulations for polymer-derived ceramic materials
10934397 · 2021-03-02 · ·

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.

Resin formulations for polymer-derived ceramic materials
10934397 · 2021-03-02 · ·

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.

METHOD OF DENSIFYING A CERAMIC MATRIX COMPOSITE USING A FILLED TACKIFIER

A method of producing an enhanced ceramic matrix composite includes applying a tackifier compound to a fiber preform. The tackifier compound includes inorganic filler particles. The method further includes modifying the tackifier compound such that the inorganic filler particles remain interspersed throughout the fiber preform, and occupy pores of fiber preform.

METHOD OF DENSIFYING A CERAMIC MATRIX COMPOSITE USING A FILLED TACKIFIER

A method of producing an enhanced ceramic matrix composite includes applying a tackifier compound to a fiber preform. The tackifier compound includes inorganic filler particles. The method further includes modifying the tackifier compound such that the inorganic filler particles remain interspersed throughout the fiber preform, and occupy pores of fiber preform.

Formulations for 3D printing of hydrosilylation-modified polysilazanes

Some variations provide a preceramic resin precursor formulation comprising: first molecules comprising at least one SiC bond and/or at least one SiN bond, wherein the first molecules include at least one silyl hydride group (SiH) available for hydrosilylation; and second molecules with at least one unsaturated carbon-carbon bond attached to a UV-active functional group. The first molecules and second molecules may be reacted, via hydrosilylation with a homogeneous or heterogeneous metal-containing catalyst, to produce third molecules comprising a hydrosilylation-modified polysilazane that contains the UV-active functional group. Many possible starting formulations are described, and methods are disclosed for carrying out the chemical reactions to generate the hydrosilylation-modified polysilazanes. The hydrosilylation-modified polysilazanes may then be 3D-printed and thermally treating to fabricate a ceramic material.

Formulations for 3D printing of hydrosilylation-modified polysilazanes

Some variations provide a preceramic resin precursor formulation comprising: first molecules comprising at least one SiC bond and/or at least one SiN bond, wherein the first molecules include at least one silyl hydride group (SiH) available for hydrosilylation; and second molecules with at least one unsaturated carbon-carbon bond attached to a UV-active functional group. The first molecules and second molecules may be reacted, via hydrosilylation with a homogeneous or heterogeneous metal-containing catalyst, to produce third molecules comprising a hydrosilylation-modified polysilazane that contains the UV-active functional group. Many possible starting formulations are described, and methods are disclosed for carrying out the chemical reactions to generate the hydrosilylation-modified polysilazanes. The hydrosilylation-modified polysilazanes may then be 3D-printed and thermally treating to fabricate a ceramic material.

FORMING FEATURES IN ADDITIVELY MANUFACTURED COMPOSITE MATERIALS USING SACRIFICIAL SUPPORT MATERIALS
20210060866 · 2021-03-04 ·

A method may include depositing a sacrificial support material on or adjacent to a build surface. The sacrificial support material may be configured to support a continuous reinforcement material during an additive manufacturing technique. The method also may include extruding the continuous reinforcement material from an additive manufacturing device such that at least a portion of the continuous reinforcement material contacts and is supported by the sacrificial support material; and removing the sacrificial support material to result in a feature defined at least in part by the continuous reinforcement material at the absence of sacrificial support material.

Preceramic Polymer Grafted Nanoparticles and Methods of Making and Using Same
20230416159 · 2023-12-28 ·

The present invention relates to preceramic polymer grafted nanoparticles and as well as methods of making and using same. Advantages of such preceramic polymer grafted nanoparticles include, reduced out gassing, desired morphology control and desirable, distinct rheological properties that are not found in simple mixtures. As a result, Applicants' preceramic polymer grafted nanoparticles can be used to provide significantly improved, items including but not limited to hypersonic vehicles, jets, rockets, mirrors, signal apertures, furnaces, glow plugs, brakes, and armor.

Preceramic Polymer Grafted Nanoparticles and Methods of Making and Using Same
20230416159 · 2023-12-28 ·

The present invention relates to preceramic polymer grafted nanoparticles and as well as methods of making and using same. Advantages of such preceramic polymer grafted nanoparticles include, reduced out gassing, desired morphology control and desirable, distinct rheological properties that are not found in simple mixtures. As a result, Applicants' preceramic polymer grafted nanoparticles can be used to provide significantly improved, items including but not limited to hypersonic vehicles, jets, rockets, mirrors, signal apertures, furnaces, glow plugs, brakes, and armor.

NOVEL HIGHLY POROUS CERAMIC AND METAL AEROGELS FROM XEROGEL POWDER PRECURSORS, AND METHODS FOR THEIR PRODUCTION AND USE

The present invention discloses novel methods for producing highly porous ceramic and/or metal aerogel monolithic objects that are hard, sturdy, and resistant to high temperatures. These methods comprise preparing nanoparticulate oxides of metals and/or metalloids via a step of vigorous stirring to prevent gelation, preparing polymer-modified xerogel powder compositions by reacting said nanoparticulate oxides with one or more polyfunctional monomers, compressing said polymer-modified xerogel powder compositions into shaped compacts, and carbothermal conversion of the shaped xerogel compacts via pyrolysis to provide the highly porous ceramic and/or metal aerogel monolithic objects that have the same shapes as to their corresponding xerogel compact precursors. Representative of the highly porous ceramic and/or metal aerogel monolithic objects of the invention are ceramic and/or metal aerogels of Si, Zr, Hf, Ti, Cr, Fe, Co, Ni, Cu, Ru, Au, and the like. Examples include sturdy, shaped, highly porous silicon carbide (SiC), silicon nitride (Si.sub.3N.sub.4), zirconium carbide (ZrC), hafnium carbide (HfC), chromium carbide (Cr.sub.3C.sub.2), titanium carbide (TiC), zirconium boride (ZrB.sub.2), hafnium boride (HfB.sub.2), and metallic aerogels of iron (Fe), nickel (Ni), cobalt (Co), copper (Cu), ruthenium (Ru), gold (Au), and the like. Said aerogel monolithic objects have utility in various applications such as, illustratively, in abrasives, in cutting tools, as catalyst support materials such as in reformers and converters, as filters such as for molten metals and hot gasses, in bio-medical tissue engineering such as bone replacement materials, in applications requiring strong lightweight materials such as in automotive and aircraft structural components, in ultra-high temperature ceramics, and the like.