Disclosed is a method of coating a high temperature fiber including depositing a base material on the high temperature fiber using atomic layer deposition, depositing an intermediate material precursor on the base material using molecular layer deposition, depositing a top material on the intermediate material precursor or the intermediate layer using atomic layer deposition, and heat treating the intermediate precursor. The intermediate material in the final coating includes a structural defect, has lower density than the top material or a combination thereof. Also disclosed are the coated high temperature fiber and a composite including the high temperature fiber.

A process for manufacturing pyrocarbon, includes forming pyrocarbon by a calefaction process from at least one C.sub.2 to C.sub.6 alcohol or polyalcohol precursor, the precursor being ethanol, rough laminar pyrocarbon being obtained by imposing a temperature of between 1250° C. and 1325° C. during calefaction.

The present invention discloses an Al.sub.2O.sub.3-based ceramic welding sealing component and a preparation method thereof, and relates to the technical field of metalized ceramic processing. The Al.sub.2O.sub.3-based ceramic welding sealing component disclosed in the present invention comprises a ceramic matrix and a metallized layer. The ceramic matrix is made from raw materials such as an inorganic fiber-aluminum oxide 3D network matrix, yttrium oxide, silicon oxide, titanium oxide, an additive, a binder and a dispersant, through steps such as preparation of the inorganic fiber-aluminum oxide 3D network matrix, mixing, pelletizing, primary sintering and secondary sintering; and the raw materials of the metallized layer comprise titanium powder, tungsten powder, molybdenum oxide, boron oxide, yttrium oxide and an organic binder. Al.sub.2O.sub.3-based ceramic welding sealing component provided by the present invention has high efficiency of space filling and tensile strength, excellent tensile strength, toughness and high-temperature resistance.

The present invention provides a method of producing a honeycomb structured body having excellent mechanical strength. The present invention relates to a method of producing a honeycomb structured body including a honeycomb fired body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween, the method including: a raw material mixing step of preparing a raw material paste containing ceria-zirconia composite oxide particles, alumina particles, an inorganic binder, and alumina fibers; a molding step of molding the raw material paste into a honeycomb molded body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween; a drying step of drying the honeycomb molded body obtained in the molding step; and a firing step of firing the honeycomb molded body dried in the drying step into a honeycomb fired body, wherein the percentage of amorphous alumina fibers in the alumina fibers for use in the raw material mixing step is 50 to 100 wt %.

The present invention provides a method of producing a honeycomb structured body having excellent mechanical strength. The present invention relates to a method of producing a honeycomb structured body including a honeycomb fired body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween, the method including: a raw material mixing step of preparing a raw material paste containing ceria-zirconia composite oxide particles, alumina particles, an inorganic binder, and inorganic fibers; a molding step of molding the raw material paste into a honeycomb molded body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween; a drying step of drying the honeycomb molded body obtained in the molding step; and a firing step of firing the honeycomb molded body dried in the drying step into a honeycomb fired body, wherein the raw material mixing step includes pre-mixing of the inorganic binder and the inorganic fibers.

A method for constructing multiple ceramic layers by winding continuous ceramic filaments of different compositions to prepare multilayer RF-transparent structures is provided. In the method, different continuous ceramic filaments are braided to construct layers with specific dielectric constants and braiding count/thickness. Layers with same or different dielectric characteristics forms a sandwich design to fulfill the desired mechanical, thermal and electrical requirements.

This invention provides resin formulations which may be used for 3D printing and pyrolyzing to produce a ceramic matrix composite. The resin formulations contain a solid-phase filler, to provide high thermal stability and mechanical strength (e.g., fracture toughness) in the final ceramic material. The invention provides direct, free-form 3D printing of a preceramic polymer loaded with a solid-phase filler, followed by converting the preceramic polymer to a 3D-printed ceramic matrix composite with potentially complex 3D shapes or in the form of large parts. Other variations provide active solid-phase functional additives as solid-phase fillers, to perform or enhance at least one chemical, physical, mechanical, or electrical function within the ceramic structure as it is being formed as well as in the final structure. Solid-phase functional additives actively improve the final ceramic structure through one or more changes actively induced by the additives during pyrolysis or other thermal treatment.

A prepreg including a support with, for more than 90% of the weight thereof, of ceramic fibers, and a thermoreversible liquefiable gel covering, at least in part, at least one portion of the ceramic fibers. The liquefiable gel including: 20% to 60% of ceramic particles and 0% to 10% of metal particles, both as percentage by volume based on the volume of the liquefiable gel; 0.2% to 10% of a thermoreversible hydrocolloid and 0% to 7% of one or more other constituents, both as a percentage by weight on the basis of the total weight of the ceramic particles and metal particles; the balance to 100% being water. It being possible for the ceramic particles and the metal particles to be replaced, partially or completely, by precursors of ceramic particles and of metal particles, respectively, capable of forming, by heat treatment above 200° C., ceramic particles and metal particles, respectively.

SiC matrix composite material, where heat-resistant long fiber such as carbon fiber is employed as a material for reinforcement and SiC is employed for the matrix, which significantly improves mechanical properties such as strength and toughness. The SiC matrix composite material, includes a SiC matrix and heat-resistant long fiber, wherein the SiC matrix includes both of alpha-type SiC and beta-type SiC, and the alpha-type SiC and the beta-type SiC are detected by micro-region X-ray diffraction with an X-ray beam diameter of no greater than 300 micrometers substantially at every region of every cross-section of the SiC matrix, the beta-type SiC has an average crystallite size that is no greater than 500 nm and greater than an average crystallite size of the alpha-type SiC, and the SiC matrix composite material has a porosity of no greater than 20% by volume.

Method for the preparation, by means of a heating technique, of a composite material composed of a matrix of at least a first oxide of at least one metal and/or at least one metalloid reinforced by reinforcements in at least a second oxide of at least one metal and/or at least one metalloid, characterised in that the following successive steps are carried out: the reinforcements are placed in at least one liquid precursor of the first oxide of at least one metal and/or at least one metalloid; said reinforcements and the liquid precursor are heated so as to form the first oxide by means of the thermal decomposition of said liquid precursor, and to deposit the first oxide thus formed around the reinforcements and between the reinforcements thus forming the matrix.