Provided are a ceramic complex having high light emission intensity and a method for producing the same. Proposed is a ceramic complex, including a rare earth aluminate fluorescent material having a composition represented by the following formula (I) and an aluminum oxide, wherein the content of the aluminum oxide is 70% by mass or more, the content of Na is 7 ppm by mass or less, the content of Si is 5 ppm by mass or less, the content of Fe is 3 ppm by mass or less, and the content of Ga is 5 pm by mass or less, relative to the total amount of the rare earth aluminate fluorescent material having a composition represented by the following formula (I) and the aluminum oxide.
(Ln.sub.1-aCe.sub.a).sub.3Al.sub.5O.sub.12   (I) wherein Ln represents at least one element selected from the group consisting of Y, Gd, Lu, and Tb; and a satisfies 0<a≤0.022.

A Cr:YAG sintered body including Al, Y, Cr, Ca, Mg, Si, and O, and component contents in the sintered body satisfying conditional expressions of 1) to 3) below, provided in the Conditional expression, each chemical symbol represents a component content (atppm).

|(Y+Ca)/(Al+Cr+Si+Mg)−0.6|<0.001;  1)

0≤(Ca+Mg)−(Cr+Si)≤50 atppm; and  2)

50≤Si≤500 atppm  3)

The embodiment of the present invention is to provide a Cr:YAG sintered body which exhibits high transparency and has a high Cr.sup.4+ conversion ratio, and its production method.

A method for manufacturing a wavelength conversion member that offers a high emission intensity and a high light conversion efficiency is provided. The method for manufacturing a wavelength conversion member includes providing a green body containing an yttrium-aluminum-garnet phosphor with a composition represented by Formula (I) below and alumina particles with an alumina purity of 99.0% by mass or more, primary-sintering the green body to obtain a first sintered body, and secondary-sintering the first sintered body by applying a hot isostatic pressing (HIP) treatment to obtain a second sintered body.

(Y.sub.1-a-bGd.sub.aCe.sub.b).sub.3Al.sub.5O.sub.12  (I)

wherein a and b satisfy 0≤a≤0.3 and 0<b≤0.022.

The sliding member according to the embodiment includes a silicon nitride sintered body that includes silicon nitride crystal grains and a grain boundary phase, in which a percentage of a number of the silicon nitride crystal grains including dislocation defect portions inside the silicon nitride crystal grains among any 50 of the silicon nitride crystal grains having completely visible contours in a 50 μm×50 μm observation region of any cross section or surface of the silicon nitride sintered body is not less than 0% and not more than 10%. The percentage is more preferably not less than 0% and not more than 3%.

In one aspect, ceramic bodies are described herein exhibiting composite architecture. Briefly, a composite ceramic body comprises a bulk region including a mixture of alpha-SiAlON and beta-SiAlON, and a surface region covering the bulk region, the surface region having a residual stress of −500 MPa to 500 MPa and a thickness of at least 5 μm.

Disclosed is a method for fabricating a solid article from a boron carbide powder comprising boron carbide particles that are coated with a titanium compound. Further disclosed herein are the unique advantages of the combined use of titanium and graphite additives in the form of water soluble species to improve intimacy of mixing in the green state. The carbon facilitates sintering, whose concentration is then attenuated in the process of forming very hard, finely dispersed TiB2 phases. The further recognition of the merits of a narrow particle size distribution B4C powder and the use of sintering soak temperatures at the threshold of close porosity which achieve post-HIPed microstructures with average grain sizes approaching the original median particle size. The combination of interdependent factors has led to B.sub.4C-based articles of higher hardness than previously reported.

A process for manufacturing a composite material part including a particulate reinforcement densified by a ceramic matrix, the process including: formation of a blank of the part to be manufactured by shaping a mixture including a binder, first ceramic or carbon particles intended to form the particulate reinforcement of the part and second ceramic or carbon particles distinct from the first particles, removal or pyrolysis of the binder present in the blank to obtain a porous preform of the part to be manufactured, and infiltration of the porosity of the preform by a molten composition including a metal in order to obtain the part.

A polycrystalline YAG sintered body, wherein, when dimensions of a smallest rectangular solid surrounding a YAG sintered body are A mm×B mm×C mm, a maximum value (A, B, C) is 150 mm or less, a minimum value (A, B, C) is more than 20 mm and 40 mm or less, and an optical loss coefficient when light of a wavelength of 300 to 1500 nm (excluding wavelengths which result in absorption of light by an additive element) is transmitted therethrough is 0.002 cm.sup.−1 or less. Moreover, a polycrystalline YAG sintered body, wherein, when dimensions of a smallest rectangular solid surrounding a YAG sintered body are A mm×B mm×C mm, a maximum value (A, B, C) is more than 150 mm and 300 mm or less, a minimum value (A, B, C) is more than 5 mm and 40 mm or less, and an optical loss coefficient when light of a wavelength of 300 to 1500 nm (excluding wavelengths which result in absorption of light by an additive element) is transmitted therethrough is 0.002 cm.sup.−1 or less. An object of an embodiment of the present invention is to provide a large and transparent polycrystalline YAG sintered body and its production method.

An object of the present disclosure is to provide the preparation and application of a low-B high-resistance high-temperature thermistor material with wide temperature range. The thermistor material uses CaCO.sub.3, Y.sub.2O.sub.3, Nb.sub.2O.sub.5, CeO.sub.2 and MoO.sub.3 as raw materials. The Ca.sub.1-yY.sub.yMoO.sub.4-xCeNbO.sub.4 (1≤x≤3, 0.01≤y≤0.2) high-temperature thermistor material having low-B high-resistance and wide temperature region is obtained by mixing grinding, calcination, cold isostatic pressing, high-temperature sintering and coating electrode. The material constant B.sub.200° C./600° C. is 1800 K-4000 K, and the resistivity at 25° C. is 8.0×10.sup.5 Ω.Math.cm-6.0×10.sup.7 Ω.Math.cm. The low-B high-resistance wide temperature range high-temperature thermistor material prepared by the disclosure has stable performance and good consistency. The thermistor material has obvious negative temperature coefficient characteristics in the range of 25° C.-1000° C. and is suitable for manufacturing wide temperature range high-temperature thermistor.

A method may include cold isostatic pressing a fused filament fabricated component comprising a plurality of roads and channels between at least some roads of the plurality of roads. The plurality of roads may include a sacrificial binder and a powder including a metal or alloy. The cold isostatic pressing reduces a presence of the channels between the at least some roads to form a compacted fused filament fabricated component. The method also may include removing substantially all the sacrificial binder from the compacted fused filament fabricated component and leave a powder component; and sintering the powder component to form a sintered component.