Abstract: A method for improving thermal efficiency of a heating device that reduces an amount of heat flowing out from a heating device 11 to the outside by installing a heat-resistant inorganic conjugated molded product 16 in and along a pathway 15 for heated gas generated from the heating device 11 without interrupting the flow of heated gas passing the pathway 15, heating the inorganic conjugated molded product 16 with the heated gas, and putting radiation heat from the heated inorganic conjugated molded product 16 back into the heating device 11, the inorganic conjugated molded product 16 being provided with an interior layer and an exterior layer, the exterior layer consisting of a coverture for inorganic materials that protects the interior layer from heated gas.

Abstract: A method for improving thermal efficiency of a heating device that reduces an amount of heat flowing out from a heating device 11 to the outside by installing a heat-resistant inorganic conjugated molded product 16 in and along a pathway 15 for heated gas generated from the heating device 11 without interrupting the flow of heated gas passing the pathway 15, heating the inorganic conjugated molded product 16 with the heated gas, and putting radiation heat from the heated inorganic conjugated molded product 16 back into the heating device 11, the inorganic conjugated molded product 16 being provided with an interior layer and an exterior layer, the exterior layer consisting of a coverture for inorganic materials that protects the interior layer from heated gas.

Abstract: A mixed polymer liquid is prepared by mixing a polycarbosilane-dissolved organic solvent with poly(methylsilane) and moderated to viscosity of 5–20 Pa·s by heat-treatment to promote partial cross-linking reaction. The mixed-polymer is then melt-spun to fiber at 250–350° C. The fiber is cured by treatment at 100–200° C. in an oxidizing atmosphere, and baked at 1000° C. or higher. Due to thermosetting action of poly(methylsilane), the mixed polymer liquid is continuously melt-spun without breakage, and SiC fiber produced in this way is useful for reinforcement of SiC composite excellent in toughness, strength and heat-resistance.

Abstract: A process for producing a SiC ceramic microtube by oxidizing the surface of an organosilicon polymer to become infusible by exposure to an ionizing radiation, extracting the uncrosslinked central portion of the fiber with an organic solvent to make a hollow silicon polymer fiber, and firing it in an inert gas so that it acquires a ceramic nature.

Abstract: A mixed polymer liquid is prepared by mixing a polycarbosilane-dissolved organic solvent with poly(methylsilane) and moderated to viscosity of 5-20 Pa.s by heat-treatment to promote partial cross-linking reaction. The mixed-polymer is then melt-spun to fiber at 250-350° C. The fiber is cured by treatment at 100-200° C. in an oxidizing atmosphere, and baked at 1000° C. or higher. Due to thermosetting action of poly(methylsilane), the mixed polymer liquid is continuously melt-spun without breakage, and SiC fiber produced in this way is useful for reinforcement of SiC composite excellent in toughness, strength and heat-resistance.

Abstract: Polycarbosilane is mixed with 5-35 wt % of polyvinylsilane to prepare a silicon-base polymer blend which is impregnated in silicon carbide fibers or fabrics to form a preceramic molding body which is exposed to an ionizing radiation to be rendered curing and then fired in an inert gas to produce a composite in which the silicon carbide matrix is reinforced with the silicon carbide fibers.

Abstract: A process for producing a SiC ceramic microtube, comprising the steps of oxidizing the surface of an organosilicon polymer to become infusible by exposure to an ionizing radiation, extracting the uncrosslinked central portion of the fiber with an organic solvent to make a hollow silicon polymer fiber, and firing it in an inert gas so that it acquires a ceramic nature.

Abstract: Polycarbosilane is mixed with 5-35 wt % of polyvinylsilane to prepare a silicon-base polymer blend which is impregnated in silicon carbide fibers or fabrics to form a preceramic molding body which is exposed to an ionizing radiation to be rendered curing and then fired in an inert gas to produce a composite in which the silicon carbide matrix is reinforced with the silicon carbide fibers.

Abstract: Ultra-high-strength refractory silicon carbide fiber having a decomposition temperature of not less than about 1800K, a breaking strength of not less than about 5 GPa, and a modulus of elasticity of not less than about 300 GPa is disclosed, which is obtained by irradiating a precursor comprising organosilicon compound fiber with an ionizing radiation in a mixed carrier gas comprising a reactive gas and a first inert gas to render the precursor infusible and calcining the irradiated precursor in a second inert gas. Irradiation damage can be minimized, and no oxygen is incorporated into the fiber.

Abstract: A super heat-resistant silicon carbide fiber has an oxygen content of less than 0.1% by weight. In a process for producing the super heat-resistant silicon carbide fiber, a precursor fiber prepared by spinning a polycarbosilane having an oxygen content of less than 0.8% by weight is irradiated with a radiation in an oxygen-free atmosphere or in vacuo to make the precursor fiber infusible. The infusibilized fiber is fired in an oxygen-free atmosphere or in vacuo at a temperature of from 1000.degree. to 2200.degree. C. without exposure to an oxidizing atmosphere; or stabilized in the same atmosphere at a temperature of from 300.degree. to 600.degree. C. without exposure to an oxidizing atmosphere and fired in an oxygen-free atmosphere or in vacuo at a temperature of from 1000.degree. to 2200.degree. C.

Abstract: The high-strength and high-toughness sinter of the present invention includes a crystal agglomerate maintaining a fibrous shape and composed of crystals of SiC and MC.sub.1-x wherein M is Ti and/or Zr and x is a number of 0 or more but less than 1. This sinter is produced by laminating an inorganic fiber of a particular inorganic material containing titanium and/or zirconium molding the laminate into a predetermined shape, and conducting heat-sintering simultaneously with the molding or after the molding in an atmosphere of a vacuum, an inert gas, a reducing gas, or a hydrocarbon gas at a temperature of 1,700 to 2,200.degree. C.

Abstract: A high purity and high strength inorganic silicon nitride continuous fiber substantially composed of Si and N with excellent properties can be provided. A method of producing the fiber is also disclosed.

Abstract: The high-strength and high-toughness sinter of the present invention comprises a crystal agglomerate maintaining a fibrous shape and composed of crystals of SiC and MC.sub.1-x wherein M is Ti and/or Zr and X is a number of 0 or more but less than 1. This sinter is produced by laminating an inorganic fiber comprising a particular inorganic material containing titanium and/or zirconium molding the laminate into a predetermined shape, and conducting heat-sintering simultaneously with the molding or after the molding in an atmosphere comprising at least one member selected from the group consisting of a vacuum, an inert gas, a reducing gas, and a hydrucoarbon gas at a temperature of 1,700.degree. to 2,200.degree. C.

Abstract: A high purity and high strength inorganic silicon nitride continuous fiber substantially composed of Si and N with excellent properties can be provided. A method of producing the fiber is also disclosed.

Abstract: A continuous inorganic fiber consisting of Si, N and O has excellent physical, chemical and electrically insulating properties, is superior to carbon fiber in wettability with metal, is low in reactivity with metal, and can be used not only as a reinforcing fiber for fiber-reinforcing type metals and fiber-reinforcing type ceramics, but also in electrical insulating materials and in heat-resistant materials.

Abstract: The invention relates to an organopolyarylsilane which comprises aromatic ring segments having a skelton mainly comprising an aromatic condensed ring structure derived from an organic solvent soluble pitch and organosilane segments randomly bonded thereto with an Si--C linkage intervening therebetween and is soluble in an organic solvent, and further relates to an SiC--C based continuous inorganic fiber exhibiting excellent heat resistant strength, oxidation resistance and electro-conductivity, which is obtained by spinning the above organopolyarylsilane into fiber, and after infusibilizing, heat-treating said fiber under a nonreactive atmosphere at a high temperature. The above organopolyarylsilane can be efficiently obtained in extremely high yields, by a process wherein low boiling substances produced by pyrolysis of the starting material, i.e.

Abstract: A molded product consisting mainly of silicon carbide and a process for mfacturing the same. This invention is to provide a product having a desired or complicated shape and a process which enables the manufacture of any such product at a drastically lower temperature than any conventional process. This object is attained by applying an organic silicon polymer having a skeleton composed mainly of carbon-silicon bonds by impregnation or adherence to a base material having a desired shape, and by burning the base material at a temperature of 700.degree. C. to 2,000.degree. C. in a vacuum or in a nonoxidizing gas atmosphere. The product of this invention has a fibrous, granular and/or firmly carbon structure in the matrix consisting mainly of SiC. The product of this invention is useful for a wide variety of applications, for example, for making heat-resistant structural members of electronic devices.

Abstract: Continuous inorganic fibers consisting substantially of Si, Zr and C and optionally of O, said fibers being composed of (1) an amorphous material consisting substantially of Si, Zr and C and optionally of O, or (2) an aggregate consisting substantially of ultrafine crystalline particles of .beta.-SiC, ZrC, a solid solution of .beta.-SiC and ZrC and ZrC.sub.1-x wherein O<x<1 and having a particle diameter of not more than 500 .ANG., in which amorphous SiO.sub.2 and ZrO.sub.2 sometimes exist in the neighborhood of these ultrafine crystalline particles, or (3) a mixture of said amorphous material (1) and said aggregate (2) of ultrafine crystalline particles. The aforesaid continuous inorganic fibers can be produced by the following steps: a first step of preparing a semi-inorganic block copolymer comprising polycarbosilane blocks having a main chain skeleton composed mainly of carbosilane units of the formula --Si--CH.sub.

Abstract: A continuous inorganic fiber consisting of Si, N and O has excellent physical, chemical and electrically insulating properties, is superior to carbon fiber in wettability with metal, is low in reactivity with metal, and can be used not only as a reinforcing fiber for fiber-reinforcing type metals and fiber-reinforcing type ceramics, but also in electrical insulating materials and in heat-resistant materials.

Abstract: A molded product consisting mainly of silicon carbide and a process for mfacturing the same. This invention is to provide a product having a desired or complicated shape and a process which enables the manufacture of any such product at a drastically lower temperature than any conventional process. This object is attained by applying an organic silicon polymer having a skeleton composed mainly of carbon-silicon bonds by impregnation or adherence to a base material having a desired shape, and by burning the base material at a temperature of 700.degree. C. to 2,000.degree. C. in a vacuum or in a nonoxidizing gas atmosphere. The product of this invention has a fibrous, granular and/or filmy carbon structure in the matrix consisting mainly of SiC. The product of this invention is useful for a wide variety of applications, for example, for making heat-resistant structural members of electronic devices.