Doped, low-temperature co-fired ceramic (LTCC) insulating substrates and related wiring boards and methods of manufacture are disclosed. The doped, LTCC insulating substrate is formed from a baked (e.g., sintered) glass-ceramic aggregate material formed from a glass material, a ceramic filler material, and a composite oxide. The crystallized glass-ceramic aggregate is then doped with Iron and/or Manganese before baking. Iron or Manganese can further reduce dielectric loss and the loss tangent of the LTCC insulating substrate formed from that glass material. The glass material becomes crystallized due to an oxide crystal phase being deposited on the glass material during baking, which reduces the dielectric losses. This may be important for the application use as wiring boards for high radio-frequency (RF) electrical circuits where low dielectric loss and loss tangent is desired to achieve a desired signal transmission delay performance.

An inductor component includes an element assembly formed of an insulator material and an inner electrode arranged in the element assembly. The insulator material contains a base material formed of an amorphous material containing B, Si, O, and K and a crystalline filler and includes a filler-poor glass portion in a region along the inner electrode. The content of the crystalline filler in the filler-poor glass portion is lower than the content of the crystalline filler in the element assembly excluding the filler-poor glass portion.

The application relates to bond materials for a grinding wheel, in particular a glass ceramic and a preparation method thereof, and a bond for the composite grinding wheel. The glass ceramic is prepared from raw materials comprising kaolin, silica, diboron trioxide, lithium superoxide, albite, potassium feldspar, talc, dolomite, phosphorus pentoxide, and yttrium oxide. A glass ceramic composed entirely of microcrystalline phases is obtained from the glass prepared by the above raw materials at 900-1020 C., achieving a complete conversion of the glass phase at a low temperature. The application also provides a bond for a composite grinding wheel, comprising glass ceramic and glass with mass ratio of (20-50):(50-80), the glass phase having a low flow temperature and, together with the glass ceramic phase, forming encapsulation of the abrasive particles, realizing low-temperature sintering of the grinding wheel. Microcrystalline phase in the bond results in high mechanical strength for the obtained grinding wheel.

Provided is a ceramic powder having precipitated therein -eucryptite or a -quartz solid solution as a main crystal phase, having an average particle diameter D.sub.50 of 20 m or less, and having a negative thermal expansion coefficient in a range of from 30 C. to 300 C.

One embodiment of the disclosure relates to a glass-ceramic with a phase assemblage comprising gillespite crystalline phase (BaFeSi.sub.4O.sub.10). According to some embodiments the glass-ceramic comprises at least one of: (a) barium silicate phase, (b) silica crystalline phase, (c) iron silicate phase.

A transparent timepiece component, in particular a watch glass, has a substantially planar or curved interior surface, and has mainly a transparent material colored by a zone of modified chemical composition within the component through an introduction of at least one coloring chemical element of the transparent material, this zone of modified chemical composition extending in one part only of the total thickness of the timepiece component.

Composite materials are provided which include a glass-ceramic matrix composition that is lightly crystallized, a fiber reinforcement within the glass-ceramic matrix composition which remains stable at temperatures greater than 1400 C., and an interphase coating formed on the fiber reinforcement. A method of making a composite material is also provided, which includes applying heat and pressure to a shape including fiber reinforcements and glass particles. The heat and pressure lightly crystallize a matrix material formed by the heat and pressure on the glass particles, forming a thermally stable composite material.

The application relates to bond materials for a grinding wheel, in particular a glass ceramic and a preparation method thereof, and a bond for the composite grinding wheel. The glass ceramic is prepared from raw materials comprising kaolin, silica, diboron trioxide, lithium superoxide, albite, potassium feldspar, talc, dolomite, phosphorus pentoxide, and yttrium oxide. A glass ceramic composed entirely of microcrystalline phases is obtained from the glass prepared by the above raw materials at 900-1020 C., achieving a complete conversion of the glass phase at a low temperature. The application also provides a bond for a composite grinding wheel, comprising glass ceramic and glass with mass ratio of (20-50):(50-80), the glass phase having a low flow temperature and, together with the glass ceramic phase, forming encapsulation of the abrasive particles, realizing low-temperature sintering of the grinding wheel. Microcrystalline phase in the bond results in high mechanical strength for the obtained grinding wheel.

An optical element reflects radiation, such as EUV radiation. The optical element includes a substrate with a surface to which a reflective coating is applied. The substrate has at least one channel through which a coolant can flow. The substrate is formed from fused silica, such as titanium-doped fused silica, or a glass ceramic. The channel has a length of at least 10 cm below the surface to which the reflective coating is applied. The cross-sectional area of the channel varies by no more than +/20% over the length of the channel.

An electrical resistor comprises a matrix composed of borosilicate containing at least one kind of alkali group atoms selected from the group consisting of Na, Mg, K, Ca, Li, Be, Rb, Sr, Cs, Ba, Fr, and Ra. The electrical resistor preferably has an electroconductive filler. A honeycomb structure comprises the electrical resistor. An electrically heated catalyst device comprises the honeycomb structure. The electrical resistor preferably has an electrical resistivity in a range from 0.0001 to 1 .Math.m and an electrical resistance increase rate in a range from 0.0110.sup.6 to 5.010.sup.4/K in a temperature range from 25 C. to 500 C.