Abstract: A visible-light-responsive three-dimensional fine cell-structured photocatalytic filter in accordance with the present invention includes a sponge-like porous structure (B) containing an anatase-type titanium oxide coating formed on a surface of a sponge-like porous structural body (A) which has a porosity of 85 vol % or more.

Abstract: A visible-light-responsive three-dimensional fine cell-structured photocatalytic filter in accordance with the present invention includes a sponge-like porous structure (B) containing an anatase-type titanium oxide coating formed on a surface of a sponge-like porous structural body (A) which has a porosity of 85 vol % or more.

Abstract: A process for producing a silicon carbide-based heat-resistant, ultra-lightweight, porous structural material having the shape of a spongy porous body.

Abstract: The present invention provides a silicon carbide-based, porous, lightweight, heat-resistant material which can retain the shape of a porous structural body formed of, for example, corrugated cardboard and provides a manufacturing method therefor. The silicon carbide-based, porous, lightweight material is produced by a process including the steps of infiltrating a slurry composed of a resin and powdered silicon into a porous structural body having a framework formed of paper such as corrugated cardboard, wood, a woven cloth, a non-woven cloth, a plastic, or the like; carbonizing the infiltrated porous structural body at 900 to 1,350° C. in an evacuated or an inert atmosphere; and performing reaction-bonding for the obtained structural body at 1,350° C. or more in an evacuated or an inert atmosphere. By the reaction-bonding, silicon carbide having superior molten silicon wettability and open pores caused by the reaction during which the reaction volume decreases are simultaneously formed.

Abstract: A super-lightweight ceramic foam with a cellular structure effectively reinforced by ceramic short fibers, which has a density of 0.2 g/cm3 or less and a sufficient strength. The ceramic foam is prepared by evenly dispersing ceramic short fibers throughout a nonaqueous solvent through the use of the reactivity of metal alkoxide with the surface of the ceramic short fibers, adding into the nonaqueous solvent an aqueous slurry containing ceramic powder dispersed therein, allowing the evenly dispersed ceramic fibers to move into an aqueous phase separately from a nonaqueous solvent phase so as to obtain an aqueous slurry containing the ceramic fibers evenly dispersed therein, and foaming and firing the aqueous slurry.

Abstract: A silicon carbide-based porous structure material maintaining the shape of a cardboard or sponge-like porous structure, with a great relative surface area, and a process for producing the same, is provided. To this end, a cardboard or sponge-like shaped framework of silicon carbide-based porous structure material is impregnated with a slurry comprising a resin, as a carbon source, and silicon powder, and subjected to reactive sintering in a vacuum or inert atmosphere, or in a nitrogen gas atmosphere, generating silicon carbide. At the same time pores are generated due to volume reduction reaction, thereby allows obtaining a silicon carbide-based porous structure material with a great relative surface area. Furthermore, excess carbon is removed from the fabricated silicon carbide-based porous structure material, and impregnated with a solution which becomes an oxide ceramic coating upon firing, whereby oxidization resistance is excellent and relative surface area is markedly improved.

Abstract: The present invention provides a silicon carbide-based heat-resistant, ultra lightweight, porous structural material having the same shape as that of a spongy porous body and also provides a process for readily producing the material. In the process of the present invention, slurry containing silicon powder and a resin is applied to the framework of the spongy porous body by an impregnation method in such a manner that interconnected pores of the porous body are not plugged with the slurry; the resulting porous body is carbonized at a temperature of 900° C. to 1320° C. in vacuum or in an inert atmosphere; the resulting porous body is subjected to reactive sintering at a temperature of 1320° C. or more in vacuum or in an inert atmosphere, whereby silicon carbide having high wettability to molten silicon is produced and open pores due to a volume reduction reaction are formed in one step; and molten silicon is infiltrated into the resulting porous body at a temperature of 1300° C. to 1800° C.

Abstract: A process produces a fiber-reinforced silicon carbide composite. The resulting composite has a high toughness where bundles of a reinforcing fiber are densely covered with glassy carbon derived from a resin to avoid deterioration of the strength, and it can easily be produced even in complicated shapes. Specifically, a fiber-reinforced silicon carbide composite is produced by preparing a fiber prepreg containing a powdered silicon and a resin and molding the prepreg to yield a green body having a desired shape, or laminating a fiber prepreg containing a resin and a woven fabric prepreg containing a powdered silicon and a resin in alternate order, and molding the laminate to yield a green body having a desired shape; carbonizing the green body at 900° C. to 1350° C. in an inert atmosphere; impregnating the carbonized body with a resin; firing the impregnated body again at 900° C. to 1350° C.

Abstract: A super-lightweight ceramic foam with a cellular structure effectively reinforced by ceramic short fibers, which has a density of 0.2 g/cm3 or less and a sufficient strength. The ceramic foam is prepared by evenly dispersing ceramic short fibers throughout a nonaqueous solvent through the use of the reactivity of metal alkoxide with the surface of the ceramic short fibers, adding into the nonaqueous solvent an aqueous slurry containing ceramic powder dispersed therein, allowing the evenly dispersed ceramic fibers to move into an aqueous phase separately from a nonaqueous solvent phase so as to obtain an aqueous slurry containing the ceramic fibers evenly dispersed therein, and foaming and firing the aqueous slurry.

Abstract: A production method of a large-size or intricately shaped lightweight ceramic molding having a bulk density of about 0.3 g/cm3 or less and having high heat resistance is accomplished by the following method.

Abstract: A process produces a fiber-reinforced silicon carbide composite. The resulting composite has a high toughness where bundles of a reinforcing fiber are densely covered with glassy carbon derived from a resin to avoid deterioration of the strength, and it can easily be produced even in complicated shapes. Specifically, a fiber-reinforced silicon carbide composite is produced by preparing a fiber prepreg containing a powdered silicon and a resin and molding the prepreg to yield a green body having a desired shape, or laminating a fiber prepreg containing a resin and a woven fabric prepreg containing a powdered silicon and a resin in alternate order, and molding the laminate to yield a green body having a desired shape; carbonizing the green body at 900° C. to 1350° C. in an inert atmosphere; impregnating the carbonized body with a resin; firing the impregnated body again at 900° C. to 1350° C.

Abstract: A fiber-reinforced silicon carbide composite is produced by preparing a fiber prepreg containing a powdered silicon and a resin and molding the prepreg to yield a green body having a desired shape, or laminating a fiber prepreg containing a resin and a woven fabric prepreg containing a powdered silicon and a resin in alternate order and molding the laminate to yield a green body having a desired shape; carbonizing the green body at 900° to 1350° C. in an inert atmosphere; subjecting the carbonized body to reaction sintering at a temperature of 1300° C. or more in vacuo or in an inert atmosphere to form open pores; and infiltrating molten silicon into the sintered body having open pores at a temperature of about 1300° to 1800° C. in vacuo or an inert atmosphere.

Abstract: The present invention provides a silicon carbide-based, porous, lightweight, heat-resistant material which can retain the shape of a porous structural body formed of, for example, corrugated cardboard and provides a manufacturing method therefor. The silicon carbide-based, porous, lightweight material is produced by a process including the steps of infiltrating a slurry composed of a resin and powdered silicon into a porous structural body having a framework formed of paper such as corrugated cardboard, wood, a woven cloth, a non-woven cloth, a plastic, or the like; carbonizing the infiltrated porous structural body at 900 to 1,350° C. in an evacuated or an inert atmosphere; and performing reaction-bonding for the obtained structural body at 1,350° C. or more in an evacuated or an inert atmosphere. By the reaction-bonding, silicon carbide having superior molten silicon wettability and open pores caused by the reaction during which the reaction volume decreases are simultaneously formed.

Abstract: The present invention provides a dense SiC-infiltrated composite material or a dense carbon-fiber-reinforced SiC-infiltrated composite material and a dense SiC-infiltrated composite material with granular carbon dispersed therein that are unlikely to bond to a carbon crucible and that have excellent heat and oxidation resistance. This composite material can be obtained by infiltrating molten carbon-silicide of Mo that is approximately expressed as Mo.sub.3 Si.sub.2 C or a eutectic mixture of carbon-silicide and silicon carbide into a silicon-carbide-based preform having 10 to 60 vol. % of continuous voids and then cooling and solidifying the melt.

Abstract: Disclosed is a method for the preparation of a fiber-reinforced silicon carbide-based composite ceramic body having outstandingly high mechanical strengths even without using any sintering aids or without undertaking the hot-press sintering method. The method comprises impregnating carbon fibers or silicon carbide fibers with a slurry containing an elementary silicon powder, an organic resin, e.g., phenolic resins, and an organosilicon polymer, e.g., polysilastyrenes, according to a specified formulation and shaping the impregnated fibers into a green body which is subjected to a calcination treatment at 1300.degree.-1500.degree. C. in an inert atmosphere under normal pressure.

Abstract: The present invention provides a SiC-MoSi.sub.2 infiltration material with high heat-resistant property, which can be used at 1500.degree. C. under atmospheric condition, can be produced at lower manufacturing temperature, and can maintain high resistance to oxidation. This ceramic composite material with high heat-resistant property can be obtained by infiltrating aluminum silicide of molybdenum, which is expressed by a formula of Mo(Al.sub.x Si.sub.1-x).sub.2 (where 0.1<x<0.5) into a porous preform of silicon carbide having porosity of 10 to 50% in volume ratio.

Abstract: A novel method is disclosed for the preparation of a silicon carbide-based composite ceramic body reinforced with carbon fibers having an outstandingly high mechanical strength. The method comprises impregnating carbon fibers with a mixture of fine silicon particles and a thermosetting resin such as a phenolic resin to give a carbon fiber compact body impregnated with the mixture, which is then subjected to a heat treatment at about 1400.degree. C. in an inert atmosphere so that the thermosetting resin is thermally decomposed to produce free carbon capable of reacting with the silicon particles without affecting the carbon fibers embedded in the matrix due to the preferential reactivity of the silicon particles with the free carbon produced from the resin thus not to decrease the recinforcing effect of the carbon fibers.

Abstract: A process for producing a .beta.-sialon.silicon carbide complex includes mixing silicon nitride and silicon carbide with an aluminum alkoxide solution or a soluble aluminum salt solution and using the resulting homogeneous mixture as a starting material in forming a sintered body. The aluminum alkoxide solution or aluminum salt solution penetrates into the surface of each particle of the silicon nitride and silicon carbide, whereby the whole surface of each nitride and carbide particle is covered with aluminum alkoxide solution or aluminum salt solution, and homogeneous mixing is achieved. Therefore, defects such as pores, clusters of large grains, or unsintered parts are eliminated and the strength of the final sintered bodies is improved.