C04B35/571

Carbon foam based silicon carbide

Producing silicon carbide carbon foam is described. The process includes filling the pores of a carbon foam with a polysiloxane resin and heating the impregnated carbon foam to high temperatures to convert the silicon in the polysiloxane resin to silicon carbon within the carbon foam.

OXIDATION-INDUCED SHAPE MEMORY FIBER AND PREPARATION METHOD AND APPLICATION THEREOF
20220017425 · 2022-01-20 ·

The present disclosure relates to an oxidation-induced shape memory fiber comprising a tension-bearing core material and/or a tension-bearing core material coated with an antioxidative coating, and an oxidizable pressure-bearing coating. The oxidizable pressure-bearing coating is coated outside the tension-bearing core material and/or the tension-bearing core material coated with an antioxidative coating; the oxidizable pressure-bearing coating is in compressive stress state and/or the tension-bearing core material coated with an antioxidative coating and the oxidizable pressure-bearing coating are in tension-compression balance state. The disclosure also relates to preparation and application thereof, the preparation is: reserving anchoring end, exerting tension force on tension-bearing core material and/or tension-bearing core material coated with an antioxidative coating, followed by coating oxidizable pressure-bearing coating thereon. The oxidation-induced shape memory fiber is applicable to high temperature oxidation environment.

PRECERAMIC IONIC SYSTEMS
20210347700 · 2021-11-11 · ·

A process of forming a Si-containing ceramic comprises forming a Si-based polymeric composition. The process includes neutralizing a charge of said Si-based polymeric composition. The process includes adding thermal energy under a controlled atmosphere to the Si-based polymeric composition. A turbine engine component comprises an airfoil and the airfoil comprises a Ceramic Matrix Composite (CMC) material.

PRECERAMIC IONIC SYSTEMS
20210347700 · 2021-11-11 · ·

A process of forming a Si-containing ceramic comprises forming a Si-based polymeric composition. The process includes neutralizing a charge of said Si-based polymeric composition. The process includes adding thermal energy under a controlled atmosphere to the Si-based polymeric composition. A turbine engine component comprises an airfoil and the airfoil comprises a Ceramic Matrix Composite (CMC) material.

PRESSED AND SELF SINTERED POLYMER DERIVED SiC MATERIALS, APPLICATIONS AND DEVICES

Organosilicon chemistry, polymer derived ceramic materials, and methods. Such materials and methods for making polysilocarb (SiOC) and Silicon Carbide (SiC) materials having 3-nines, 4-nines, 6-nines and greater purity. Processes and articles utilizing such high purity SiOC and SiC.

PRESSED AND SELF SINTERED POLYMER DERIVED SiC MATERIALS, APPLICATIONS AND DEVICES

Organosilicon chemistry, polymer derived ceramic materials, and methods. Such materials and methods for making polysilocarb (SiOC) and Silicon Carbide (SiC) materials having 3-nines, 4-nines, 6-nines and greater purity. Processes and articles utilizing such high purity SiOC and SiC.

Oxidation-resistant fiber coatings and related methods

A method of manufacturing a coated reinforcing fiber for use in Ceramic Matrix Composites, the method comprising pre-oxidizing a plurality of silicon-based fibers selected from the group consisting of silicon carbide (SiC) fibers, silicon nitride (Si.sub.3N.sub.4) fibers, SiCO fibers, SiCN fibers, SiCNO fibers, and SiBCN fibers at between 700 to 1300 degrees Celsius in an oxidizing atmosphere to form a silica surface layer on the plurality of silicon-based fibers, forming a plurality of pre-oxidized fibers; applying a rare earth orthophosphate (REPO.sub.4) coating to the plurality of pre-oxidized fibers; and heating the plurality of REPO.sub.4 coated pre-oxidized fibers at about 1000-1500 degrees Celsius in an inert atmosphere to react the REPO.sub.4 with the silica surface layer to form a rare earth silicate or disilicate. The pre-oxidizing step may be 0.5 hours to about 100 hours. The heating step may be about 5 minutes to about 100 hours.

Method to process a ceramic matrix composite (CMC) with a protective ceramic coating

A method of producing a ceramic matrix composite including a protective ceramic coating thereon comprises applying a surface slurry onto an outer surface of an impregnated fiber preform. The surface slurry includes particulate ceramic solids dispersed in a flowable preceramic polymer comprising silicon, and the impregnated fiber preform comprises a framework of ceramic fibers loaded with particulate matter. The flowable preceramic polymer is cured, thereby forming on the outer surface a composite layer comprising a cured preceramic polymer with the particulate ceramic solids dispersed therein. The cured preceramic polymer is then pyrolyzed to form a porous ceramic layer comprising silicon carbide, and the impregnated fiber preform and the porous ceramic layer are infiltrated with a molten material comprising silicon. After infiltration, the molten material is cooled to form a ceramic matrix composite body with a protective ceramic coating thereon.

Method to process a ceramic matrix composite (CMC) with a protective ceramic coating

A method of producing a ceramic matrix composite including a protective ceramic coating thereon comprises applying a surface slurry onto an outer surface of an impregnated fiber preform. The surface slurry includes particulate ceramic solids dispersed in a flowable preceramic polymer comprising silicon, and the impregnated fiber preform comprises a framework of ceramic fibers loaded with particulate matter. The flowable preceramic polymer is cured, thereby forming on the outer surface a composite layer comprising a cured preceramic polymer with the particulate ceramic solids dispersed therein. The cured preceramic polymer is then pyrolyzed to form a porous ceramic layer comprising silicon carbide, and the impregnated fiber preform and the porous ceramic layer are infiltrated with a molten material comprising silicon. After infiltration, the molten material is cooled to form a ceramic matrix composite body with a protective ceramic coating thereon.

OXIDATION-RESISTANT FIBER COATINGS AND RELATED METHODS

A method of manufacturing a coated reinforcing fiber for use in Ceramic Matrix Composites, the method comprising pre-oxidizing a plurality of silicon-based fibers selected from the group consisting of silicon carbide (SiC) fibers, silicon nitride (Si.sub.3N.sub.4) fibers, SiCO fibers, SiCN fibers, SiCNO fibers, and SiBCN fibers at between 700 to 1300 degrees Celsius in an oxidizing atmosphere to form a silica surface layer on the plurality of silicon-based fibers, forming a plurality of pre-oxidized fibers; applying a rare earth orthophosphate (REPO.sub.4) coating to the plurality of pre-oxidized fibers; and heating the plurality of REPO.sub.4 coated pre-oxidized fibers at about 1000-1500 degrees Celsius in an inert atmosphere to react the REPO.sub.4 with the silica surface layer to form a rare earth silicate or disilicate. The pre-oxidizing step may be 0.5 hours to about 100 hours. The heating step may be about 5 minutes to about 100 hours.