Methods for making an inorganic sheet (7), a sintered ceramic sheet and a sintered multilayered ceramic composite, an inorganic sheet (7), sintered ceramic sheet and a sintered multilayered ceramic composite obtainable by such methods, and an apparatus configured to carry out such methods.

A holding material (3) for a catalytic converter is interposed in a gap between a catalyst carrier (1) and a metal casing (2) receiving the catalyst carrier. The holding material (3) includes a mat including alumina fiber (3A) and mullite fiber (3B), wherein the alumina fiber (3A) and the mullite fiber (3B) are unitarily collected to form the holding material (3) having a predetermined thickness.

The purpose of the present invention is to provide a method for manufacturing a ceramic substrate hardly causing cracks and damages and the like attributed to pushing pressure and the like since the strength of the above-mentioned ceramic substrate is higher than that of a conventional one even in the case of manufacturing a large size ceramic substrate capable of placing a semiconductor wafer with a large diameter and the like. The present invention is to provide a method for manufacturing a ceramic substrate having a conductor formed on the surface thereof or internally thereof, including the steps of: firing a formed body containing a ceramic powder to produce a primary sintered body; and performing an annealing process to the primary sintered body at a temperature of 1400°C to 1800°C, after the preceding step.

The object of the present invention is to provide a sintered aluminum nitride substrate which has a via hole and an internal electrically conductive layer, having high thermal conductivity and high adhesion strength between the sintered aluminum nitride substrate and the internal electrically conductive layer or the via hole and having other excellent properties. The substrate according to the invention comprising an internal electrically conductive layer, at least one electrically conductive via hole formed between the internal electrically conductive layer and at least one surface of the substrate, wherein the thermal conductivity of the aluminum nitride sintering product at 25°C is 190 W/mK or more, and the adhesion strength between the aluminum nitride sintering product and the internal electrically conductive layer is 5.0 kg/mm² or more.

There is provided a metal/ceramic bonding article which ensures sufficient thermal shock resistance and has a substrate having a small outside dimension and which has both high reliability and compactness. The metal/ceramic bonding article comprises: a ceramic substrate; and a metal plate bonded to the ceramic substrate via a brazing filler metal, wherein the brazing filler metal protrudes from the bottom face of the metal plate by a length which is longer than 30 µm and which is 250 µm or less, or wherein the brazing filler metal protrudes from the bottom face of the metal plate by a length which is 25 % or more of the thickness of the metal plate.

A method of producing a material having a layer of ceramic as a first component, a layer of a metal as a second component and an intermediate layer lying between said layers and including said first and second components in continuously gradient ratios so that the properties of the material may change continuously; including a step to form said intermediate layer by igniting the mixture of powders of metallic and nonmetallic constitutive elements of said ceramic and powder of said metal and causing synthetic reaction of the powder mixture.