Abstract: A piston head structure in which a piston head made of a ceramic is firmly secured to the top portion of a metallic piston body through the medium of a metallic ring fitted to the lower part of the piston head. In assembling, the ceramic piston head to which the metallic ring is fitted beforehand is secured to the top portion of the piston body by a shrink fit or, alternatively, the assembly of the ceramic piston head and the metallic ring is inserted to the metallic material of the piston body during casting of the latter, and the cast piston body is then subjected to necessary mechanical processing. In this structure, the separation of the piston head from the piston body is prevented due to the close fit of the ceramic piston head and the metallic ring to the metallic piston body. Such a fit prevents separation even when the piston body is expanded due to the heat generated during operation of the engine.

Abstract: A disc brake having a pair of pistons composed of a Devitroceramics having a heat conductivity of about 1.times.10.sup.-3 cal/cm.sec..degree.C. to about 4.times.10.sup.-2 cal/cm.sec..degree.C., a bend strength of about 5 kg/mm.sup.2 to about 55 kg/mm.sup.2, a Vickers' hardness of about 400, and a density of smaller than about 4.0 g/cm.sup.3. A method of manufacturing the disc brake comprises incorporating into the disc brake a pair of pistons which are prepared by mixing the component materials of the Devitroceramics, melting them to a homogeneous molten state, molding the molten materials into a piston-shaped article, annealing the article for crystallization and heating the article.

Abstract: Metallized layers are formed respectively on the surfaces to be joined of the ceramic members by performing metallized treatment on the surfaces, and then, these metallized layers are pressed against each other, and under pressure are diffusion-bonded at high temperature. A metal foil which can form a solid solution with the metallized layers can be interposed between the metallized layers before diffusion-bonding. This method can be used to manufacture an oxygen sensor element.

Abstract: The present invention relates to an integrated catalyst component comprising an integrated catalyst housed within a molded ceramic fiber retaining sleeve held together by a cylindrical compression ring and end rings attached to the ends of said compression ring, and to a method of assembling said component.