Abstract: This vacuum cleaning device is provided with: a vapor chamber in which vapor of a hydrocarbon-based cleaning agent is generated; a condensation chamber; a first heat exchanger in which heat exchange between the vapor and a heating medium is carried out; a cleaning chamber in which a workpiece can be cleaned under vacuum by the condensed cleaning agent that has been generated in the condensation chamber; a compressor that adiabatically compresses and further heats the heating medium that was heated by the first heat exchanger; a second heat exchanger that carries out heat exchange between the heating medium heated by the compressor and the hydrocarbon-based cleaning agent in the vapor chamber; and a vacuum unit that further cools the heating medium that has been cooled by the second heat exchanger by forcing vacuum expansion of the heating medium.

Abstract: This vacuum cleaning device is provided with: a vapor chamber in which vapor of a hydrocarbon-based cleaning agent is generated; a condensation chamber; a first heat exchanger in which heat exchange between the vapor and a heating medium is carried out; a cleaning chamber in which a workpiece can be cleaned under vacuum by the condensed cleaning agent that has been generated in the condensation chamber; a compressor that adiabatically compresses and further heats the heating medium that was heated by the first heat exchanger; a second heat exchanger that carries out heat exchange between the heating medium heated by the compressor and the hydrocarbon-based cleaning agent in the vapor chamber; and a vacuum unit that further cools the heating medium that has been cooled by the second heat exchanger by forcing vacuum expansion of the heating medium.

Abstract: A thermal barrier coating system comprising a metal substrate, a metal bonding layer and a ceramics thermal barrier layer wherein the ceramics thermal barrier layer has a columnar structure of a stabilized zirconia containing a stabilizer or a stabilized ZrO2—HfO2 solid solution containing a stabilizer, and comprises 0.1 to 10 mol % of lanthanum oxide.

Abstract: A thermal barrier coating system comprising a metal substrate, a metal bonding layer and a ceramics thermal barrier layer wherein the ceramics thermal barrier layer has a columnar structure of a stabilized zirconia containing a stabilizer or a stabilized ZrO2—HfO2 solid solution containing a stabilizer, and comprises 0.1 to 10 mol % of lanthanum oxide.

Abstract: A thermal barrier coating system comprising a metal substrate, a metal bonding layer and a ceramics thermal barrier layer wherein the ceramics thermal barrier layer has a columnar structure of a stabilized zirconia containing a stabilizer or a stabilized ZrO2—HfO2 solid solution containing a stabilizer, and comprises 0.1 to 10 mol % of lanthanum oxide.

Abstract: The present invention relates to a method for producing a porous silicon nitride sintered body having high strength and low thermal conductivity, which comprises of adding more than 10 volume % of rodlike beta-silicon nitride single crystals with a larger mean diameter than that of a silicon nitride raw powder into a mixture comprising the silicon nitride raw powder and a sintering additive, preparing a formed body with rodlike beta-silicon nitride single crystals oriented parallel to the casting plane according to a forming technique such as sheet casting and extrusion forming, sintering said formed body to develop elongated silicon nitride grains from the added rodlike beta-silicon nitride single crystals as nuclei and obtain the sintered body with the elongated grains being dispersed in a complicated state.

Abstract: An object of the present invention is to provide a high-porosity, high-strength porous silicon nitride having great tolerance with respect to strain and stress, and a method for producing the same, and the present invention relates to a high-porosity, high-strength porous silicon nitride having great tolerance with respect to strain and stress, characterized in that rodlike grains of silicon nitride with a minor diameter of 0.5 to 10 .mu.m and an aspect ratio of 10 to 100 are oriented in a single direction, and the rest of the structure other than the rodlike grains consists solely of pores with a porosity of 5 to 30%, and further the above-mentioned porous silicon nitride is produced by mixing rodlike particles of silicon nitride with a minor diameter of 0.5 to 10 .mu.

Abstract: The present invention relates to a silicon nitride sintered body having a remarkably increased strain-to-fracture, a low elasticity and high strength, characterized by consisting of a layered structure of alternating porous silicon nitride layers 1 to 1000 .mu.m thick with a porosity of 5 to 70 volume % and dense silicon nitride layers 1 to 1000 .mu.m thick with a porosity of less than 5 volume %, being layered as materials with optional tiers. In addition, this invention relates to a method for producing the silicon nitride sintered body as described above, which comprises of forming dense layers and porous layers by sheet casting or extrusion forming so as to prepare the layers to be capable of 1 to 1000 .mu.m thick after sintering, stacking them to obtain layered materials with optional tiers and sintering them at 1600.degree. to 2100 .degree. C. under a nitrogen atmosphere.