Abstract: There is provided a method for activating a solid acid salt electrolyte capable of enhancing the proton conductivity of solid acid salts at a temperature at or below a point of phase transition to the super proton conducting phase, through humidity control, by taking advantage of this phenomenon. The method for activating a solid acid salt electrolyte, comprising the steps of preparing a solid acid salt electrolyte composed of cations and anions, and forcibly keeping the surface of the solid acid salt electrolyte at humidity in a range of 10 to 100% at temperature in a range of 10 to 80° C., whereby proton conductivity in the solid acid salt electrolyte is improved.

Abstract: A method of producing a solid electrolyte (3, 13) is disclosed wherein solid electrolyte material is prepared having a composition expressed by a formula: (1-x) ZrO2 {xSc2O3 (where x is a number equal to or greater than 0.05 and equal to or less than 0.15), and a spark plasma method is carried out to sinter solid electrolyte material, resulting in a solid electrolyte. Such spark plasma method is executed by applying first compression load, equal to or less that 40 MPa, to solid electrolyte material, to sinter the solid electrolyte material to obtain sintered material, which is then cooled by applying second compression load, less than first compression load, to the sintered material, resulting in a solid electrolyte.

Abstract: A method of producing a solid electrolyte (3, 13) is disclosed wherein solid electrolyte material is prepared having a composition expressed by a formula: (1-x) ZrO2 {xSc2O3 (where x is a number equal to or greater than 0.05 and equal to or less than 0.15), and a spark plasma method is carried out to sinter solid electrolyte material, resulting in a solid electrolyte. Such spark plasma method is executed by applying first compression load, equal to or less that 40 MPa, to solid electrolyte material, to sinter the solid electrolyte material to obtain sintered material, which is then cooled by applying second compression load, less than first compression load, to the sintered material, resulting in a solid electrolyte.

Abstract: Disclosed is a shape memory alloy wire subjected to a cold drawing work, which comprises a shape memory alloy in a martensitic phase which assumes an austenitic phase or a martensitic phase through phase transformation temperatures, has a diameter of 60 ?m or less, and has a reverse transformation termination temperature of at least 250° C. By using the alloy wire, a composite material having the alloy wire embedded in a resin having a molding temperature as high as 180° C., such as a glass fiber reinforced resin or a carbon fire reinforced resin, without fixing of both wire ends.

Abstract: A piezoelectric material includes a polycrystalline piezoelectric compound having a component composition defined as Sr2-xCaxNaNb5O15, where x=0.05 to 0.35, and at least one rare earth oxide compound selected from the group consisting of Y2O3, La2O3, Dy2O3, Nd2O3, Yb2O3, Sm2O3, Er2O3, Gd2O3 and Pr6O11 to be added to the piezoelectric compound by 0.5 to 3.0 wt %. Moreover, a method of manufacturing the piezoelectric material includes blending ceramic materials, synthesizing, milling, pressing and sintering processes. In the synthesizing process, calcining is conducted at a temperature in a range from 1,050° C. to 1,150° C. for 2 to 12 hours in the atmosphere. And the sintering process includes first firing at temperature in a range from 1,180° C. to 1,270° C. for 4 to 8 hours in the atmosphere, and second firing at a temperature in a range from 1,370° C. to 1,400° C. for 10 to 75 hours in the atmosphere.

Abstract: A solid electrolyte material contains an A site-deficient complex oxide represented by a chemical formula A1-&agr;BO3-&dgr;, in which a B site contains at least Ga. This solid electrolyte material has stability, high oxide-ion conductivity at low temperature and high toughness. A method of manufacturing the solid electrolyte material, comprises: mixing oxide materials of respective constituent elements; baking temporarily the mixed materials at 1100 to 1200° C. for 2 to 10 hours; grinding the temporarily baked materials to powder; molding the powder; and sintering the molded powder. A solid oxide fuel cell, has: the solid electrolyte material; a cathode electrode formed on one surface of the solid electrolyte material; and an anode electrode formed on the other surface of the solid electrolyte material. The solid oxide fuel cell has a stable and long operation at low temperature.

Abstract: A piezoelectric material includes a polycrystalline piezoelectric compound having a component composition defined as Sr2-xCaxNaNb5O15, where x=0.05 to 0.35, and at least one rare earth oxide compound selected from the group consisting of Y2O3, La2O3, Dy2O3, Nd2O3, Yb2O3, Sm2O3, Er2O3, Gd2O3 and Pr6O11 to be added to the piezoelectric compound by 0.5 to 3.0 wt %. Moreover, a method of manufacturing the piezoelectric material includes blending ceramic materials, synthesizing, milling, pressing and sintering processes. In the synthesizing process, calcining is conducted at a temperature in a range from 1,050° C. to 1,150° C. for 2 to 12 hours in the atmosphere. And the sintering process includes first firing at temperature in a range from 1,180° C. to 1,270° C. for 4 to 8 hours in the atmosphere, and second firing at a temperature in a range from 1,370° C. to 1,400° C. for 10 to 75 hours in the atmosphere.

Abstract: A solid electrolyte used in a cell and represented by the following formula: La(1−x−y)LnxAyGa(1−z)BzO3−0.5(x+y+z) where Ln is at least one element selected from the group consisting of Gd, Sm and Nd; A is Ba; B is Mg; x is 0.1; y is 0.1; and z is 0.2, wherein the solid electrolyte is formed of particles whose means diameter is within a range of from 4 to 10 &mgr;m, the solid electrolyte being produced by a method comprising: (a) mixing lanthanum oxide, gallium oxide, oxide of at least one rate earth element selected from the group consisting of Gd, Sm and Nd, barium oxide and magnesium oxide to form a mixture; (b) firing the mixture in air at a temperature ranging from 1100 to 1200° C. for a time ranging from 2 to 8 hours to accomplish synthesizing a compound material; (c) pulverizing the compound material; (d) compacting the pulverized compound material; (e) adjusting mean diameter of the pulverized compound material within a range of from 0.5 to 0.

Abstract: A solid electrolyte material contains an A site-deficient complex oxide represented by a chemical formula A1-&agr;BO3-&dgr;, in which a B site contains at least Ga. This solid electrolyte material has stability, high oxide-ion conductivity at low temperature and high toughness. A method of manufacturing the solid electrolyte material, comprises: mixing oxide materials of respective constituent elements; baking temporarily the mixed materials at 1100 to 1200° C. for 2 to 10 hours; grinding the temporarily baked materials to powder; molding the powder; and sintering the molded powder. A solid oxide fuel cell, has: the solid electrolyte material; a cathode electrode formed on one surface of the solid electrolyte material; and an anode electrode formed on the other surface of the solid electrolyte material. The solid oxide fuel cell has a stable and long operation at low temperature.

Abstract: A sintered silicon nitride excellent in high temperature performance is produced by the following method: First, silicon nitride powder and oxide of at least one element selected from elements in the group IIIb of a periodic table are mixed with each other to obtain a mixture. The silicon nitride powder contains silicon oxide in an amount ranging from 0.1% by weight of the silicon nitride powder to a value not more than a content of the silicon oxide. Second, the mixture is compacted to form a compact. Finally, the compact is fired in atmosphere of nitrogen at a pressure ranging from 5 to 200 atmosphere (atm) and a temperature ranging from 1800.degree. to 2000.degree. C. to obtain a sintered silicon nitrite having a bulk density not less than 95% of a theoretical density of the sintered silicon nitride.

Abstract: The invention relates to a sintered composite of silicon carbide and silicon nitride. The sintered composite includes a polycrystalline matrix and polycrystalline aggregates dispersed in the matrix. The matrix includes silicon carbide grains, first silicon-nitride grains and a first sintering aid thereof. Each of the aggregates includes second silicon-nitride grains and a second sintering aid thereof. The aggregates have an average diameter within a range from 10 .mu.m to 50 .mu.m. This average diameter is defined as a diameter of a circle having an area which is the same as the average area of the aggregates on a two-dimensional section of the sintered composite. The sintered composite is light in weight and superior in strength and fracture toughness at high temperature as well as at room temperature.

Abstract: A method for producing a sintered silicon carbide and sialon composite includes the following steps in the sequence: sintering a mixture including .alpha.-sialon powder, .alpha.-silicon nitride powder and .beta.-silicon carbide powder by hot pressing at a first predetermined temperature; and resintering the sintered mixture at a pressure of nitrogen gas ranging from 100 to 2000 atmosphere and at a second predetermined temperature 100.degree. to 200.degree. C. higher than the first predetermined temperature.

Abstract: A method for producing a sintered silicon carbide and silicon nitride base composite which is suitable for a material for automotive engine parts. The method is comprised of compacting a mixture including, as major components, powder of .beta.-type silicon carbide and powder of .alpha.-type silicon nitride to form a compact. The compact is first sintered at ordinary pressure, and then resintered at a pressure of nitrogen gas ranging from 10 to 2000 atmosphere and at a temperature higher 100.degree. to 200.degree. C. than that in the ordinary pressure sintering, thereby obtaining the sintered composite high in strength and toughness.

Abstract: An exhaust apparatus for a combustion equipment comprises an exhaust liner which includes a tubular member. The tubular member is formed by weaving or braiding a SiC fiber. A SiC is infiltrated thereinto out of the inner wall portion of the tubular member by the CVD method, thus obtaining an exhaust liner including a SiC Fiber/CVD - SiC composite. The density of SiC is greater in the inner wall of the exhaust liner than in the outer wall thereof.

Abstract: An oxygen sensing element having a ceramic substrate, a layer of an oxygen ion conductive solid electrolyte such as zirconia containing a stabilizing oxide such as yttria, and a pair of electrode layers formed on one side of the solid electrolyte layer so as to be spaced from each other. To prevent a significant change in the output characteristic of the element caused by diffusion of the stabilizing oxide from the solid electrolyte layer into the ceramic substrate, there is a barrier layer which intervenes between the substrate and the solid electrolyte layer at least in a region between the two electrode layers. The barrier layer is formed of a ceramic material such as the above mentioned solid electrolyte or a metal such as platinum, or has a double-layer structure consisting of a metal layer in direct contact with the substrate and an outer layer formed of a ceramic material.

Abstract: Disclosed is a paste containing an electrically conducting powder, which is a mixture of a platinum powder and a ceramic material powder in a proportion in the range from 51:49 to 78:22 by volume and has a specific surface area of 1.0 to 10.0 m.sup.2 /g, uniformly dispersed in an organic liquid vehicle in a proportion in the range from 70:30 to 50:50 by weight. A cavity in a ceramic substrate of an electric device having two, or more, conducting parts separately fixed to the substrate is filled up with this paste, and subsequently the substrate is fired to sinter the paste in the cavity into a conducting solid filler which provides electrical connection between the two conducting parts with low resistance and close and firm contact with the conducting parts and wall surfaces defining the cavity.

Abstract: In an oxygen sensor comprising an oxygen ion conductive solid electrolyte, an electronically conductive reference electrode layer formed on one side of the electrolyte layer, an electronically conductive measurement electrode layer formed on the other side of the electrolyte layer, and a partition layer of an electrochemically inactive material formed on the outer side of the reference electrode layer, at least one of the reference and measurement electrode layers has a plurality of openings through which two layers which put therebetween the one of the electrode layers are united with each other.

Abstract: In an oxygen sensor comprising an oxygen ion conductive solid electrolyte, an electronically conductive reference electrode layer formed on one side of the electrolyte layer, an electronically conductive measurement electrode layer formed on the other side of the electrolyte layer, and a partition layer of an electrochemically inactive material formed on the outer side of the reference electrode layer, at least one of the reference and measurement electrode layers has a plurality of openings through which two layers which put therebetween the one of the electrode layers are united with each other.

Abstract: A method of producing a flat solid electrolyte layer of a flat film type oxygen sensor is disclosed. The method comprises in steps, (a) preparing first and second electrolyte pastes each containing stabilizer, the content of stabilizer in the first electrolyte paste being smaller than that in the second electrolyte paste, (b) applying the first electrolyte paste onto an electrode layer and then applying the second electrolyte paste onto the outer face of the first electrolyte paste to form a layered paste heap on the electrode layer, and (c) firing the layered paste heap to form a solid electrolyte layer on the electrode layer. With this production method, the stabilizer is uniformly and homogeneously distributed into the body of the fired electrolyte layer.