Kyocera Corporation

Hidehiro Takenoshita

Satoshi Toyoda

Shuichi Iida

Mizuho Oota

Hitomi Ochiai

Masayuki Moriyama

Chisato Ishida

Kenichi Furutachi

Mami Iida

Tsuyoshi Komatsu

A corrosion-resistant member according to the present disclosure includes a substrate that is composed of an aluminum-oxide-based ceramic and a covering layer that is composed of an O&#x2014;Al&#x2014;C layer that is located on the substrate.

Corrosion-resistant member

A corrosion-resistant member may include alumina ceramics containing &#x3b1;-alumina and anorthite. The alumina ceramics may contain 0.4% by mass or more of Ca and Si in total in terms of CaO and SiO, respectively, and a mass ratio of CaO/SiOmay fall within a range of 0.5 to 2. Moreover, a ratio B/A of X-ray diffraction peak intensity B for (004) plane of the anorthite to X-ray diffraction peak intensity A for (104) plane of the &#x3b1;-alumina in a surface of the alumina ceramics, may be 0.01 or more.

A ferrite sintered body includes a crystal grain of a Ni&#x2014;Zn ferrite and a grain boundary thereof, in which Ti is unevenly distributed in an outer region of the crystal grain, the outer region extending from an interface of the crystal grain to a length of 20% of a major axis of the crystal grain.

Ferrite sintered body, ferrite core, and coil component

The high-withstanding-voltage member includes an alumina sintered compact containing alumina as a main crystal. Furthermore, the alumina sintered compact exhibits a peak intensity of 5000 or less at a wavelength of about 330 nm when measured by a cathode luminescence method.

High-withstanding-voltage alumina sintered compact and high-withstanding-voltage member

There are provided a dielectric ceramic having a high Qf value in a relative permittivity &#x2208;r range of 35 to 45, and a small absolute value of a temperature coefficient &#x3c4;f which indicates change of the resonant frequency in a wide temperature range from a low temperature range to a high temperature range, and a dielectric filter having the dielectric ceramic. A dielectric ceramic includes: a main component, molar ratios &#x3b1;, &#x3b2;, and &#x3b3; satisfying expressions of 0.240&#x2266;&#x3b1;&#x2266;0.470, 0.040&#x2266;&#x3b2;&#x2266;0.200, 0.400&#x2266;&#x3b3;&#x2266;0.650, and &#x3b1;+&#x3b2;+&#x3b3;=1 when a composition formula of the main component is represented as &#x3b1;ZrO.&#x3b2;SnO.&#x3b3;TiO; and Mn, a content of Mn in terms of MnObeing greater than or equal to 0.01% by mass and less than 0.1% by mass with respect to 100% by mass of the main component.

Dielectric ceramic and dielectric filter having the same

A ferrite sintered body having an improved strength and a noise filter including the same are provided. A ferrite sintered body includes 1 mol % to 10 mol % Cu on CuO basis, a spinel-structured crystal containing Fe, Zn, Ni, Cu and O as a main phase, and Cu compound particles present at a grain boundary, having an average particle diameter of 0.5 &#x3bc;m to 10 &#x3bc;m. The ferrite sintered body includes the Cu compound particles present at a grain boundary. It is thereby possible to suppress the grain growth of the crystals serving as the main phase to attain a morphology formed of fine crystals, and also inhibit the propagation of destruction of the grain boundary, thus making it possible to achieve a ferrite sintered body with an improved strength.

Ferrite sintered body and noise filter including the same

A ferrite sintered body is composed of an oxide containing, as metal element, at least Fe and Zn and at least one selected from Ni, Cu and Mn. This sintered body contain Fe of 42 to 50 mol % in terms of FeO, and Zn of 15 to 35 mol % in terms of ZnO. When the Zn concentration in the sintered body interior is taken to be 1, the Zn concentration in the surface vicinity is 0.8 to 12. This increases the surface resistance of the ferrite sintered body and lowers its core loss.

Ferrite sintered body, manufacturing method thereof, ferrite core using same, and ferrite coil

A ferrite core comprising a sintered oxide containing at least 48.6 to 53.9 mol % of Fe on FeObasis, 12.3 to 35.2 mol % of Ni on NiO basis and 16.4 to 37.0 mol % of Zn on ZnO basis as metal elements, and contains a crystal phase comprising two or more kinds of solid solutions selected from NiFeO, ZnFeOand FeFeO, wherein full width at half maximum of a diffraction peak, of crystal phase of which diffraction angle 2&#x3b8; is in a range from 34.6 to 36.4&#xb0; as measured by X-ray diffraction analysis using Cu&#x2014;K&#x3b1; beam, is 0.4&#xb0; or less.

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Kirishima, Japan

Hidehiro Takenoshita