A ceramic substrate includes a substrate main body, and a conductor layer provided inside of the substrate main body. The substrate main body includes an insulator layer that is ceramics composed of aluminum oxide, and a composite oxide layer of aluminum and silicon, the composite oxide layer being formed between the insulator layer and the conductor layer.

The method includes the steps of: a) selecting particles with particular slenderness ratios and diameters from SiC powder to serve as selected SiC material powder; b) coating a PVA coating on particles of the selected SiC material powder so that the PVA coating and the selected SiC material powder are combined into a particulate ceramic material; c) pressing the particulate ceramic material into a ceramic base body; d) sintering the ceramic base body to form a fixed shape and forming completely continuous channels from an inside to a surface thereof by cooling; and e) infiltrating the ceramic base body with molten aluminum. The ceramic composite material made by the method includes a ceramic base body having completely continuous channels from an inside to a surface thereof; an aluminum filler filled in the channels; and an aluminum coating disposed on the ceramic base body and integratedly connecting with the aluminum filler.

The invention relates to a copper/ceramic composite comprising—a ceramic substrate which contains aluminum oxide, —a coating which lies on the ceramic substrate and which is made of copper or a copper alloy, wherein the copper or the copper alloy has a particle size number distribution with a median value d.sub.50, an arithmetic mean value d.sub.arith, and a symmetry value S(Cu)=d.sub.50/d.sub.arith; the aluminum oxide has a particle size number distribution with a median value d.sub.50, an arithmetic mean value d.sub.arith, and a symmetry value S(Al.sub.2O.sub.3)=d.sub.50/d.sub.arith; and S(Al.sub.2O.sub.3) and S(Cu) satisfy the following condition: 0.7≤S(Al.sub.2O.sub.3)/S(Cu)≤1.4.

A method of forming a doped substrate comprises heating a substrate comprising a layer of a dopant on at least one surface to a predetermined temperature; applying a predetermined degree of isostatic external pressure on the surface of said substrate at said predetermined temperature for a time sufficient to induce thermal migration of the dopant into the substrate to provide a doped substrate; and removing the isostatic pressure and cooling the doped substrate to about room temperature. The substrate is a glass material, a single crystal material, a poly-crystalline material, a ceramic material, or a semiconductor material, and the substrate may be optically transparent. The dopant comprises one or more transition metals, one or more rare earth elements, or a combination of both. The layer of a dopant comprises one or more segregated layers of distinct chemical species. The isostatic pressure and elevated temperature may be applied simultaneously or sequentially.

A ceramic material, a varistor and methods for forming a ceramic material and a varistor are disclosed. In an embodiment, a ceramic material includes ZnO as a main component and additives selected from the group consisting of an Al.sup.3+-containing solution, a Ba.sup.2+-containing solution, and at least one compound containing a metal element, wherein the metal element is selected from the group consisting of Bi, Sb, Co, Mn, Ni, Y, and Cr.

A ceramic matrix composite (CMC) is formed using a three-dimensional (3-D) woven preform by removing the set of sacrificial fibers from the 3-D woven preform and allowing a metal or metal alloy infiltrate the 3-D woven preform. The 3-D woven preform is formed by a method that includes providing a woven layer comprising a first set of ceramic fibers oriented in a first (x) direction woven with a second set of ceramic fibers oriented in a second (y) direction; stacking a plurality of woven layers on top of each other, said woven layers providing a two-dimensional (2-D) preform; weaving a set of sacrificial fibers in a third (z) direction with the 2-D preform, said weaving providing the 3-D woven preform; and shaping the 3-D woven preform into a predetermined shape.

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 of producing a melt infiltrated ceramic matrix composite (CMC) article that includes the steps of: forming a ceramic fiber preform; optionally, rigidizing the ceramic fiber preform with a fiber interphase coating via a Chemical Vapor Infiltration (CVI) process, infiltrating a ceramic slurry into the porous body or preform, conducting one or more secondary operations, and finally, melt infiltrating the preform with molten silicon or a silicon alloy to form the CMC article. The infiltration of a ceramic slurry into a ceramic fiber preform to form a green body is performed along with the use of convection and/or conduction as heat transfer mechanisms, such that the ceramic slurry does not require the incorporation of a pre-gelation material in order for the slurry to remain within the green body during subsequent processing steps.

A method for fabricating a porous ceramic heating body, and a method of fabricating a heating body. The method for fabricating includes, in sequence, mixing, ball-milling, defoaming, molding, and drying, pore-forming agent discharging, sintering, and electrode leading. The whole method is simple, and by using a box furnace to sinter the green body under an oxidizing atmosphere and normal pressure, the fabricated ceramic heating body is heated uniformly and the heating efficiency is high.

A method for fabricating a ceramic matrix composite component having a deltoid region is provided. The method includes providing a porous ceramic preform. The porous ceramic preform includes a layer-to-layer weave of ceramic fibers that forms a modified layer-to-layer woven core and at least one 2-dimensional layer of ceramic fibers that is disposed adjacent to the modified layer-to-layer woven core. The porous ceramic preform is formed into a ceramic matrix composite body having the deltoid region such that the modified layer-to-layer woven core extends through the deltoid region.