Tohoku University

Other

Kabushiki Kaisha Toshiba

Mitsubishi Denki Kabushiki Kaisha

Onoda Cement Co., Ltd.

Japan Metals & Chemicals Co., Ltd.

Onada Cement Co., Ltd

Onada Alc Co., Ltd.

Onoda Alc Co., Ltd.

Hideaki Takahashi

Tetsuo Shoji

Hiroyuki Abe

Takashi Watanabe

Hiroaki Niitsuma

Katsuto Nakatsuka

Koichi Tsukiyama

Chiharu Wada

Keitaro Kunugiza

Koichi Tsutsumi

Satoshi Teramura

Masahiko Suzuki

Naotake Mohri

Nagao Saito

Ko Sato

Hideki Sekine

Kazushige Kimura

Morihiko Takanohashi

Fumihiko Chiba

Masamitsu Muramatsu

Kiyoshi Saitoh

Kazuo Hayashi

This invention provides a hot forming mold made of xonotlite group materials such as xonotlite, or wollastonite made therefrom which are known as a heat-resisting materials. By hot pressing these materials to high bulk density e.g., 0.6 to 2.20, a mold suitable for use in hot forming, having increased bending strength and hardness can be efficiently made. Such molds are made by filter pressing an aqueous slurry of xonotlite, then drying the pressed product to remove moisture at a temperature less than about 700.degree. C., and then cutting out the mold for use in molding plastic, glass and the like. By heat treating this mold product at a temperature of about 700.degree. to 1200.degree. C. the mold so produced can be subjected to machining and can be used as a mold for superplastic forming aluminum, titanium and the like.

Hot forming mold and method of manufacturing the same

This invention provides a hot forming mold made of xonotlite group materials such as xonotlite, or wollastonite made therefrom, which are known as a heat-resisting materials. By hot pressing these material to high bulk density e.g., 0.6 to 2.20, a mold suitable for use in hot forming, having increased sending strength and hardness can be efficiently made. Such molds are made by filter pressing an aqueous slurry of xonotlite, then drying the pressed product to remove moisture at a temperature less than about 700.degree. C., and then cutting out the mold for use in molding plastic, glass and the like. By heat treating this mold product at a temperature of about 700.degree. to 1200.degree. C. the mold so produced can be subjected to machining and can be used as a mold for superplastic forming aluminum, titanium and the like.

A method for forming a surface layer on a base material to be processed by electric discharge process, said method being characterized in that the electric discharge process is conducted in liquid or liquefied gas by use of a metalloid or a metal as an electrode for electric discharge process to thereby form on the surface of said base material a layer having an amorphous alloy structure or a very fine crystal structure.

Method for forming surface layer by electric discharge process

An underground chemical reactor having a closed loop reactor which includes at least a reaction component inlet tube and a reaction product outlet tube and a casing pipe consisting of a double or triple tube and the circulating system for a reaction component such as raw material sludge and a direct chemical reaction system for the reaction component with the deep underground high temperature water of a hot water source formed by a natural hot water source of an artificial crushed zone at a depth of more than 1,000 m, thereby an oxide magnetic material such as soft ferrite, hard ferrite, each kind of ceramics or heat-resisting materials such as xonotlite, dielectric materials, clay materials may be made in the underground chemical reactor.

Underground chemical reactor

The disclosed method introduces a pressure effectivity factor h, so as to continuously determine fracture toughness K.sub.IC of rock during core boring by using the equation of

Method for determining fracture toughness of rock by core boring

A method of collecting geothermal steam using Acoustic Emission Microseismic Activity (AE/MA) measurement includes the steps of (a) surveying an AE wave emitted in subsurface cracks to obtain the size of a water permeable geothermal reservoir by analyzing the AE wave, (b) further surveying the AE wave emitted in and around the periphery of the geothermal reservoir, (c) operating the wellhead valve of the geothermal well connected with the geothermal reservoir, thereby extending or preventing the extension of the geothermal reservoir in accordance with the information obtained in step (a) and/or step (b), thereby stably obtaining a predetermined quantity of steam of high quality. Thus, the method can stably obtain geothermal steam of high quality by accurately surveying or monitoring subsurface cracks by an AE measurement technique and propagating the subsurface cracks or suppressing the propagation of the cracks.

Method of collecting geothermal steam using AE/MA measurement

Earth's crustal stress is measured by drilling a bore-hole in rock body, producing a longitudinal crack at a selected portion thereof with or without a natural traverse crack through intermittent application of hydraulic pressure thereat while measuring the pressure at different stages of crack production, producing an artificial traverse cracks through the use of a prenotch, determining orientations of the cracks thus produced by inspecting the bore-hole surface conditions, and numerically analyzing the crack orientations and the pressures at different stages of crack production.

Method of measuring crustal stress by hydraulic fracture based on

A method of detecting embrittlement of a heat-resisting steel comprises evaluating the brittleness of the heat-resisting steel on the basis of the repassivation current value obtained by (a) connecting the steel as the anode of an anode polarization curve measuring apparatus wherein an aqueous solution containing an organic acid and an alkylbenzene sulfonic acid or its salt is used as an electrolytic solution; and (b) raising the anode potential from an active region to a passive region and thereafter lowering the anode potential to measure the repassivation current value.

Method of detecting embrittlement of heat-resisting steel

Growing community of inventors

Sendai, Japan

Hideaki Takahashi