Kyocera Corporation

Satoshi Toyoda

Hidehiro Takenoshita

Shuichi Iida

Mizuho Oota

Takahiro Ueno

Mami Iida

Kenichi Furutachi

Tsuyoshi Komatsu

Kentaro Kikuchi

A heat-resistant member () according to the present disclosure contains alumina as a main component, and magnesium aluminate and boron. The content percentage of the magnesium aluminate at the surface is higher than the content percentage of the magnesium aluminate in a surface layer section located directly below the surface.

Heat-resistant member

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.

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.

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Kirishima, Japan

Satoshi Toyoda