Abstract: A ceramic heater element 10 includes an insulating substrate 101, and a heating resistor 102 embedded in the insulating substrate 101. The insulating substrate 101 contains a main phase formed of ?-SiAlON or a multiphase SiAlON of ?-SiAlON and ?-SiAlON; a grain boundary phase containing a rare earth element; and a silicide of at least one species selected from among Cr, W, Mo, V, and Fe. The heating resistor 102 contains a main phase formed of an electrically conductive compound containing at least one species selected from among silicide, nitride, and carbide of Mo, and silicide, nitride, and carbide of W; ?-SiAlON or a multiphase SiAlON of ?-SiAlON and ?-SiAlON; and a grain boundary phase containing a rare earth element.

Abstract: A gas sensor element (100) including a detection portion (150) including a solid electrolyte body (105) and a pair of electrodes (104) and (106) disposed on the solid electrolyte body; and a porous protection layer (20) covering the detection portion. The porous protection layer includes an inner porous layer (21) and an outer porous layer (23); the inner porous layer is higher in porosity than the outer porous layer; the inner porous layer contains, as main components, ceramic particles (21a), and ceramic fiber filaments (21b) which are mainly formed of a ceramic material and which have a mean fiber length of 70 to 200 ?m; and the amount of the ceramic fiber filaments is 25 to 75 vol % on the basis of the total amount of the ceramic particles and the ceramic fiber filaments, the total amount being taken as 100 vol %.

Abstract: An insulator for spark plug with a main constituent of alumina and containing silicon includes a grain boundary phase positioned between alumina particles. The grain boundary phase contains: a group 2A element; a rare earth element; and at least one kind of zirconium, titanium, chrome, niobium, manganese, and iron (a first element). Assuming that a total amount of the rare earth element is X (mass %), a total amount of the group 2A element is Y (mass %), and a total amount of the first element is Z (mass %), the following are met: 0.40?Y/X?2.00 0.10?Z/X?0.40.

Abstract: A spark plug including an insulator containing an Al component, in terms of oxides, 89 mass % or more and a Ti component, in terms of oxides, more than 0 mass % and 0.2 mass % or less, characterized in that the insulator is formed of an alumina-based sintered material which contains, in a grain boundary phase present between alumina crystal grains, a first crystal phase containing at least one species selected from among an La component, an Nd component, a Pr component, a Y component, an Er component, a Yb component, and an Lu component, and a second crystal phase containing at least one species of Group 2 element components, an Al component and an Si component.

Abstract: A gas sensor element (100) includes a laminate of a detection element (300) and a heater (200), and a porous protection layer (20) covering a forward end portion thereof. The laminate has a measuring chamber (107c) into which a gas-to-be-measured is introduced via a diffusion resistor (115). The porous protection layer includes an inner porous layer (21), and an outer porous layer (23). The inner porous layer has a higher porosity than the outer porous layer and the diffusion resistor. As viewed in a plurality of 100 ?m×100 ?m regions a1 to a3 and b1 to b3 on sections of the inner porous layer and the diffusion resistor, respectively, a pore diameter greater than the greatest pore diameter CDIF in the regions of the diffusion resistor exists in each of the regions of the inner porous layer.

Abstract: There is provided a gas sensor element for detecting the concentration of a specific gas component in gas under measurement, which includes a plate-shaped element body and a porous protection layer. The element body has, at one end portion thereof, a gas sensing portion formed with a solid electrolyte substrate and a pair of electrodes. The porous protection layer has a porous structure formed of ceramic particles and surrounds at least the circumference of the one end portion of the element body. In the present invention, the porous protection layer has an inner region, an intermediate region and an outer region laminated together in order of mention from the element body toward the outside. The intermediate region has a porosity lower than those of the inner and outer regions. There is also provided a gas sensor with such a gas sensor element.

Abstract: A ceramic sintered body includes tungsten carbide, zirconia, and alumina. The content of the tungsten carbide is 20 to 50 vol %, and the content of the zirconia is 5 to 25 vol %. The crystal phase of the zirconia is a tetragonal crystal or a mixture of tetragonal and monoclinic crystals. The ceramic sintered body does not substantially include Ti compounds. The average particle diameter of the tungsten carbide, the average particle diameter of the zirconia, and the average particle diameter of the alumina are all 1 ?m or less.

Abstract: A sintered body containing alumina crystal particles and zirconia crystal particles as main components includes the tetragonal crystal particles as the zirconia crystal particles. The zirconia crystal particles satisfy relations 0%?A?3%, 3%?B?22% and 77%?C?96%,where A, B and C are as defined herein.

Abstract: An insulator for spark plug with a main constituent of alumina and containing silicon includes a grain boundary phase positioned between alumina particles. The grain boundary phase contains: a group 2A element; a rare earth element; and at least one kind of zirconium, titanium, chrome, niobium, manganese, and iron (a first element). Assuming that a total amount of the rare earth element is X (mass %), a total amount of the group 2A element is Y (mass %), and a total amount of the first element is Z (mass %), the following are met: 0.40?Y/X?2.00 0.10?Z/X?0.40.

Abstract: A gas sensor element (100) including a detection portion (150) including a solid electrolyte body (105) and a pair of electrodes (104) and (106) disposed on the solid electrolyte body; and a porous protection layer (20) covering the detection portion. The porous protection layer includes an inner porous layer (21) and an outer porous layer (23); the inner porous layer is higher in porosity than the outer porous layer; the inner porous layer contains, as main components, ceramic particles (21a), and ceramic fiber filaments (21b) which are mainly formed of a ceramic material and which have a mean fiber length of 70 to 200 ?m; and the amount of the ceramic fiber filaments is 25 to 75 vol % on the basis of the total amount of the ceramic particles and the ceramic fiber filaments, the total amount being taken as 100 vol %.

Abstract: A ceramic sintered body includes tungsten carbide, zirconia, and alumina. The content of the tungsten carbide is 20 to 50 vol %, and the content of the zirconia is 5 to 25 vol %. The crystal phase of the zirconia is a tetragonal crystal or a mixture of tetragonal and monoclinic crystals. The ceramic sintered body does not substantially include Ti compounds. The average particle diameter of the tungsten carbide, the average particle diameter of the zirconia, and the average particle diameter of the alumina are all 1 ?m or less.

Abstract: A conductive sintered oxide which includes: a conductive crystal phase having a perovskite structure represented by (RE1-cSrc)MdO3, in which RE is a group of elements consisting of Yb and/or Lu and at least one element selected from Group IIIA elements excluding Yb, Lu and La, and M is a group of elements consisting of Al and at least one element selected from Groups IVA, VA, VIA, VIIA and VIII, a first insulating crystal phase represented by RE2O3, and a second insulating crystal phase represented by SrAl2O4. The conductive crystal phase has a coefficient c satisfying 0.18<c<0.50 and has a coefficient d satisfying 0.67?d?0.93. A content of a third insulating crystal phase represented by RE4Al2O9, the content of which may be zero, is smaller than the content of each of the first and second insulating crystal phases.

Abstract: A relay includes: a pair of fixed terminals, each being arranged to have a fixed contact on a one-end face; a movable contact member arranged to have a pair of movable contacts that are correspondingly opposed to the respective fixed contacts; and a driving structure operated to move the movable contact member. In a moving direction of the movable contact member, a side where the fixed contacts are located is called a first side, and a side where the movable contacts are located is called a second side. The movable contact member includes: a center section located between the pair of movable contacts and located on the second side relative to the movable contacts; and a pair of extended sections located between the center section and the pair of movable contacts and extended in a direction including a component of the moving direction.

Abstract: A gas sensor element and a gas sensor incorporating the gas sensor element. The gas sensor element (100) includes a detection portion (150) including a solid electrolyte body (105) and a pair of electrodes (104) and (106) disposed on the solid electrolyte body; and a porous protection layer (20) covering the detection portion. The porous protection layer includes an inner porous layer (21) and an outer porous layer (23). The inner porous layer has a higher porosity than the outer porous layer. Further, the inner porous layer contains, as main components, ceramic particles (21a), and ceramic fiber filaments (21b), and the amount of the ceramic fiber filaments is 25 to 75 vol % based on the total amount of the ceramic particles and the ceramic fiber filaments taken as 100 vol %.

Abstract: A relay includes: a plurality of fixed terminals arranged to have fixed contacts; and a movable contact member arranged to have a plurality of movable contacts that are correspondingly opposed to the respective fixed contacts. The relay further includes: a driving structure operated to move the movable contact member such that the respective movable contacts come into contact with the corresponding fixed contacts; a plurality of first vessels provided corresponding to the respective fixed terminals and arranged to have insulating property; a second vessel joined with the plurality of first vessels; and an air-tight space formed by the plurality of fixed terminals, the plurality of first vessels and the second vessel to allow the movable contact member and the respective fixed contacts to be placed therein.

Abstract: A conductive sintered oxide including: a first crystal phase represented by RE14Al2O9 and a second crystal phase having a perovskite structure represented by (RE21-cSLc)(AlxM1y)O3. RE1 is a first element group consisting of Yb and/or Lu and at least one element selected from Group IIIA elements excluding Yb, Lu and La. RE2 is a second element group consisting of at least one element selected from Group IIIA elements excluding La and including at least one of the elements constituting the first element group RE1. SL is an element group consisting of at least one of Sr, Ca and Mg and which includes Sr as a main element, and M1 is an element group consisting of at least one element selected from Groups IVA, VA, VIA, VIIA and VIII excluding Cr. The coefficient c is in the range of 0.18<c<0.50, and the coefficients x and y are in the range of 0.95?x+y?1.1.

Abstract: A sintered electroconductive oxide forming a thermistor element has a first crystal phase having a composition represented by RE14Al2O9 and a second crystal phase having a perovskite structure represented by (RE21-aSLa)MO3. The factor a of the second crystal phase is: 0.18<a<0.50, wherein RE1 represents at least one of Yb and Lu and at least one species selected from among group 3A elements excluding Yb, Lu, and La; RE2 represents at least one species selected from among group 3A elements excluding La and which contains at least one species selected from the group RE1; M represents Al and at least one species selected from group 4A to 7A, and 8 elements; and SL represents Sr, Ca, and Mg, with at least Sr being included at a predominant proportion by mole.

Abstract: A spark plug that is equipped with an insulator that has a stem portion on a front end side, a center electrode, and a main metal member that retains the insulator at an engaging projection portion, wherein an inner diameter DIN of the engaging projection portion, the maximum outer diameter dOUT of the stem portion, which faces an inner circumferential surface of the engaging projection portion, its inner diameter dIN, and dielectric constant ? of the insulator satisfy the condition of “(DIN?dOUT)/2?0.40 (mm)”, “(dOUT?dIN)/2?1.65 (mm)”, and “??9.4”.

Abstract: A sintered body containing alumina crystal particles and zirconia crystal particles as main components includes the tetragonal crystal particles as the zirconia crystal particles. The zirconia crystal particles satisfy relations 0%?A?3%, 3%?B?22% and 77%?C?96%, where A, B and C are as defined herein.

Abstract: A relay includes: a pair of fixed terminals, each being arranged to have a fixed contact on a one-end face; a movable contact member arranged to have a pair of movable contacts that are correspondingly opposed to the respective fixed contacts; and a driving structure operated to move the movable contact member. In a moving direction of the movable contact member, a side where the fixed contacts are located is called a first side, and a side where the movable contacts are located is called a second side. The movable contact member includes: a center section located between the pair of movable contacts and located on the second side relative to the movable contacts; and a pair of extended sections located between the center section and the pair of movable contacts and extended in a direction including a component of the moving direction.