One aspect of the present disclosure provides a composite sheet including a porous sintered ceramic component having a thickness of less than 2 mm and a resin filled into pores of the sintered ceramic component, wherein the resin is a semi-cured product of a resin composition including a compound having a cyanate group and the content of triazine rings in the resin is 0.6 to 4.0 mass %.

A composite sheet includes porous a nitride sintered body having a thickness of less than 2 mm and resins filled in pores of the nitride sintered body, and has a main surface having a maximum height roughness Rz of less than 20 μm. A method for manufacturing the composite sheet includes an impregnating step of impregnating pores of a porous the nitride sintered body having a thickness of less than 2 mm with a resin composition, a smoothing step of smoothing the resin composition attached to a main surface of the nitride sintered body to obtain a resin-impregnated body in which a part of the main surface is exposed, and a curing step of heating the resin-impregnated body to cure or semi-cure the resin composition impregnated in the pores to obtain the composite sheet.

A composite sheet includes porous a nitride sintered body having a thickness of less than 2 mm and resins filled in pores of the nitride sintered body, and has a main surface having a maximum height roughness Rz of less than 20 μm. A method for manufacturing the composite sheet includes an impregnating step of impregnating pores of a porous the nitride sintered body having a thickness of less than 2 mm with a resin composition, a smoothing step of smoothing the resin composition attached to a main surface of the nitride sintered body to obtain a resin-impregnated body in which a part of the main surface is exposed, and a curing step of heating the resin-impregnated body to cure or semi-cure the resin composition impregnated in the pores to obtain the composite sheet.

Provided is a boron nitride sintered body in which an average number of lump particles having a particle size of 30 μm or more formed by aggregation of primary particles of boron nitride is 3 or less in a cross-sectional image including 100 or more particles observed at a magnification of 500 times with a scanning electron microscope. A method of manufacturing a boron nitride sintered body includes a nitriding step of sintering a raw material powder containing boron carbide in a nitrogen-containing atmosphere to obtain a fired product containing boron carbonitride, a pulverizing step of pulverizing the fired product to obtain a boron carbonitride powder having a specific surface area of 12 m.sup.2/g or more, and a firing step of molding and heating a blend containing the boron carbonitride powder and a sintering aid to obtain a boron nitride sintered body.

Provided is a boron nitride sintered body in which an average number of lump particles having a particle size of 30 μm or more formed by aggregation of primary particles of boron nitride is 3 or less in a cross-sectional image including 100 or more particles observed at a magnification of 500 times with a scanning electron microscope. A method of manufacturing a boron nitride sintered body includes a nitriding step of sintering a raw material powder containing boron carbide in a nitrogen-containing atmosphere to obtain a fired product containing boron carbonitride, a pulverizing step of pulverizing the fired product to obtain a boron carbonitride powder having a specific surface area of 12 m.sup.2/g or more, and a firing step of molding and heating a blend containing the boron carbonitride powder and a sintering aid to obtain a boron nitride sintered body.

Semi-crystalline polymer-ceramic composites and methods. The ceramic-polymer composites, in powder and/or pellet forms, comprise a plurality of core-shell particles, where: each of the core-shell particles comprises a core and a shell around the core; the core comprises a ceramic that is selected from the group of ceramics consisting of: Al.sub.2O.sub.3, ZrO.sub.2, and combinations of Al.sub.2O.sub.3 and ZrO.sub.2; and the shell comprises a semi-crystalline polymer selected from the group of semi-crystalline polymers consisting of: polyphenylene sulfide (PPS), polyaryl ether ketone (PAEK), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), semi-crystalline polyimide (SC PI), and semi-crystalline polyamide (SC Polyamide). The core-shell particles can be in a powder form (e.g., a dry powder). In pellet form, shells of adjacent core-shell particles are joined to resist separation of the adjacent core-shell particles and deformation of a respective pellet. Methods of forming a ceramic-polymer composite comprise: superheating a mixture of the semi-crystalline polymer (PPS, PAEK, PBT, PP, PE, SC PI, and SC Polyamide), solvent, and the ceramic (Al.sub.2O.sub.3 and/or ZrO.sub.2), to dissolve the semi-crystalline polymer in the solvent; agitating the superheated mixture while substantially maintaining the mixture at an elevated temperature and pressure; and cooling the mixture to cause the semi-crystalline polymer to precipitate on the particles of the ceramic and thereby form a plurality of the present semi-crystalline polymer-ceramic core-shell particles. Methods of molding a part comprise subjecting a powder of the present semi-crystalline polymer-ceramic core-shell particles that substantially fills a mold to a first pressure while the powder is at or above a first temperature above a melting temperature (T.sub.m) of the semi-crystalline polymers.

Semi-crystalline polymer-ceramic composites and methods. The ceramic-polymer composites, in powder and/or pellet forms, comprise a plurality of core-shell particles, where: each of the core-shell particles comprises a core and a shell around the core; the core comprises a ceramic that is selected from the group of ceramics consisting of: Al.sub.2O.sub.3, ZrO.sub.2, and combinations of Al.sub.2O.sub.3 and ZrO.sub.2; and the shell comprises a semi-crystalline polymer selected from the group of semi-crystalline polymers consisting of: polyphenylene sulfide (PPS), polyaryl ether ketone (PAEK), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), semi-crystalline polyimide (SC PI), and semi-crystalline polyamide (SC Polyamide). The core-shell particles can be in a powder form (e.g., a dry powder). In pellet form, shells of adjacent core-shell particles are joined to resist separation of the adjacent core-shell particles and deformation of a respective pellet. Methods of forming a ceramic-polymer composite comprise: superheating a mixture of the semi-crystalline polymer (PPS, PAEK, PBT, PP, PE, SC PI, and SC Polyamide), solvent, and the ceramic (Al.sub.2O.sub.3 and/or ZrO.sub.2), to dissolve the semi-crystalline polymer in the solvent; agitating the superheated mixture while substantially maintaining the mixture at an elevated temperature and pressure; and cooling the mixture to cause the semi-crystalline polymer to precipitate on the particles of the ceramic and thereby form a plurality of the present semi-crystalline polymer-ceramic core-shell particles. Methods of molding a part comprise subjecting a powder of the present semi-crystalline polymer-ceramic core-shell particles that substantially fills a mold to a first pressure while the powder is at or above a first temperature above a melting temperature (T.sub.m) of the semi-crystalline polymers.

To provide a ceramic composite and a production method therefor allowing ease of processing to be improved and fracture toughness to be improved simultaneously. The invention includes the steps of: preparing at least a liquid-form resin and a ceramic sintered body which has been sintered at a temperature which is 700° C. to 100° C. less than a sintering temperature at which a theoretical density is obtained; immersing the ceramic sintered body in the liquid-form resin, causing the liquid-form resin to infiltrate the ceramic sintered body; and hardening the infiltrated liquid-form resin to obtain a ceramic composite having a relative density of between 40% and 90% by causing the resin to infiltrate. Gaps where no resin has infiltrated are formed in the ceramic composite.

To provide a ceramic composite and a production method therefor allowing ease of processing to be improved and fracture toughness to be improved simultaneously. The invention includes the steps of: preparing at least a liquid-form resin and a ceramic sintered body which has been sintered at a temperature which is 700° C. to 100° C. less than a sintering temperature at which a theoretical density is obtained; immersing the ceramic sintered body in the liquid-form resin, causing the liquid-form resin to infiltrate the ceramic sintered body; and hardening the infiltrated liquid-form resin to obtain a ceramic composite having a relative density of between 40% and 90% by causing the resin to infiltrate. Gaps where no resin has infiltrated are formed in the ceramic composite.

Disclosed is a moderator for moderating neutrons, including a substrate and a surface treatment layer or a dry inert gas layer or a vacuum layer coated on the surface of the substrate, wherein the substrate is prepared from a moderating material by a powder sintering device through a powder sintering process from powders or by compacting powders into a block, and the moderating material includes 40% to 100% by weight of aluminum fluoride; wherein the surface treatment layer is a hydrophobic material; and the surface treatment layer or the dry inert gas layer or the vacuum layer is used for isolating the substrate from the water in the environment in which the substrate is placed. The surface treated moderator can avoid the hygroscopic or deliquescence of the moderating material during use, improve the quality of the neutron source and prolong the service life.