To provide a faraday rotator using a TGG ceramic sintered compact and a light isolator using the faraday rotator such that the influence of scattered light can be relatively reduced and overall characteristics degradation for the entire light isolator is minimized so that a high extinction ratio of at least 38 dB or greater is achieved. [Solution] The faraday rotator according to the present invention uses a TGG ceramic sintered compact having an average particle diameter of 0.2 to 5.0 m, and has a transmission beam diameter of 0.3 mm or more, the TGG ceramic sintered compact being preferably annealed.

Provided is a method for preparing a grain boundary insulation-type dielectric. The method includes the steps of obtaining a titanic acid compound and a ferroelectric having a value less than a melting point of the titanic acid compound; obtaining a mixture by adding the ferroelectric material to the titanic acid compound; and sintering the mixture at a temperature equal to or more than a melting point of the ferroelectric material.

A method is provided for producing an article which is transparent to IR wavelength in the region of 4 m to 9 m. The method includes the steps of (a) Producing ultra-fine powders of ZnS, (b) followed by pretreatment of the ultra-fine powders under reduced gas conditions including H2, H2S, N2, Ar and mixtures there of (c) followed by vacuum (310.sup.6 torr) treatment to remove oxygen and sulfates adsorbed to the surface disposing a plurality of nano-particles on a substrate, wherein said nanoparticles comprise ZnS with ultra-high purity of cubic phase; (b) subjecting the nano-particles to spark plasma sintering thereby producing a sintered ZnS product with IR transmission reaching 75% in the wavelength range of 4 m to 9 m.

Disclosed is a manufacturing method of a gas sensor element. The gas sensor element has a plate shape extending in a direction of an axis thereof and includes: a detection portion arranged on a front end side of the gas sensor element to detect a specific gas component in a gas under measurement; and a porous protective layer formed around the detection portion. The manufacturing method of the gas sensor element is characterized in that the porous protective layer is formed by press forming of a raw material powder.

A method of manufacturing a component (100) having a main part (101) and a projecting feature (104,114), the method comprising providing a shaped void (210) corresponding to the component, locating a pre-formed element (214) in a feature region of the shaped void which corresponds to the projecting feature, locating powder (212) within the shaped void; and forming the element and the powder into the component such that the element creates at least a part of the projecting feature.

A heater tube for molten metal immersion 1 has a cylindrical heater housing part 4 equipped with a closed end 2 and an open end 3, wherein the heater housing part 4 comprises silicon nitride, a compound comprising yttrium, and a compound comprising magnesium. The heater housing part 4 has a surface roughness Ra of an outer circumferential surface of the heater housing part 4 is between 0.5 m and 10 m, inclusive.

There is provided an oxide sintered body including indium, tungsten and zinc, wherein the oxide sintered body includes a bixbite type crystal phase as a main component and has an apparent density of higher than 6.5 g/cm.sup.3 and equal to or lower than 7.1 g/cm.sup.3, a content rate of tungsten to a total of indium, tungsten and zinc is higher than 1.2 atomic % and lower than 30 atomic %, and a content rate of zinc to the total of indium, tungsten and zinc is higher than 1.2 atomic % and lower than 30 atomic %. There are also provided a sputtering target including this oxide sintered body, and a semiconductor device including an oxide semiconductor film formed by a sputtering method by using the sputtering target.

Provided is an apparatus that includes a molding die for producing a sintered body. The molding die is configured for cold isostatic pressing and includes a knockdown mold frame comprised of plural frame members and a bottom plate provided in contact with the knockdown mold frame. An upper punch is provided to be movable along the inner surface of the knockdown mold frame. The frame members configured to be movable relative to each other to accommodate an expansion of a green body which takes place at the time of reducing the pressure after the completion of pressing.

A production process includes introducing the material to be moulded into a mould, placing the mould in an envelope comprising a vacuum port; creating a low pressure in the envelope by formation of a gas flow through the vacuum port; deforming the mould; stopping the gas flow; and applying pressure on at least a portion of the mould, optionally with interposition of the envelope, at least after the gas flow is stopped.

A method of producing ceramic wafer includes a forming step and processing step. The processing step includes forming positioning notch or positioning, flat edge and edge profile, which avoids the ceramic wafers to have processing defect during cutting, grinding, and polishing, for increasing yield. The ceramic particles for producing ceramic wafer include nitride ceramic powder, oxide ceramic powder, and nitride ceramic powder. The ceramic wafer has low dielectric constant, insulation, and excellent heat dissipation, which can be applied for the need of semiconductor process, producing electric product and semiconductor equipment.