Abstract: In the permeable structure, which is built up of sheets, continuous channels are arranged in rows and between the rows of channels are formed flow spaces which at opposite sides are bounded bit cover plates. In the flow spaces (4) at least two successive transverse bridges (6) are arranged on the same level, the transverse bridges (6) in at least half of the sheets having a different length (B) and the channels (1) extending essentially perpendicular to the flow spaces (4).

Abstract: In the heat exchanger module, produced by stacking sheet cards provided with openings and subsequently joining the individual cards of the card stack, each sheet card (2) or group of sheet cards of the stack is arranged rotated about a common axis by an angle .alpha. of between 0.degree. and 30.degree. with respect to the preceding sheet card (2) or group of sheet cards, the openings (3) forming helical channels (4).

Abstract: In the finned-tube heat exchanger of silicon-infiltrated silicon carbide, in which the tubes of a tube bundle, with the cooling medium flowing around the tubes, are arranged mutually parallel in a housing provided with an inlet and outlet for the cooling medium, the tubes of the tube bundle are joined to one another by fins. The fins have apertures and are arranged transversely to the tube bundle.

Abstract: In a process for producing ceramic sliding bodies containing hollow chambers from a green solid parent body and a green film body containing hollow chambers, the green film body and the green solid parent body are laminated together, the organic constituents are removed by heating from the green body so obtained or the organic constituents are carbonized. Subsequently, the body is fired or siliconized. According to the invention, the green solid parent body is produced from the ceramic green material of the film body, in particular from film residues which are produced in producing the green film body containing hollow chambers. The film residues may be comminuted to form a powder in a mill.

Abstract: In a heat exchanger module of fired ceramic material produced from a stack of punched and laminated green ceramic cards, the stack comprises at least two cards. The cards have first cut-outs (1) which, in stacked cards, form tubular channels (12) and second cut-outs (2, 4, 7, 8) which are positioned around the first cut-outs (1) and which, in stacked cards, partially overlap with the second cut-outs (2, 4, 7) of adjacent cards. Channels (13) which lie in the plane of the cards and surround the tubular channels (12) are thus formed.

Abstract: Process and apparatus for manufacturing heat exchangers from ceramic sheets, wherein different flow channels are stamped from or pressed into the sheets, and the formed sheets are joined together with a laminating agent. The stacking of the individual sheets is effected using apparatus in which the sheets are transported to the forming means, applicator means and laminating means by horizontally and vertically displaceable, rotatable and pivotable suction plates. The organic component of the ceramic sheets is expelled from the heat exchanger block obtained in two heating steps with an intermediate forming operation to bring the heat exchanger block to its final dimensions, and the block then fired between 1,200.degree. to 1,700.degree. C. The actual sintering temperature depends on the particular ceramic used, which may comprise Si.sub.3 N.sub.4, SiC, cordierite and/or semiconductive barium titanate compounds.

Abstract: By use of new ion conducting but non-electron conducting mixed crystal compounds of the type sodium zirconium phosphatosilicate as the ceramic board material for electronic circuitry it is possible to provide full integration of electronic, electro-chemical and optical components, because the boards simultaneously constitute the solid electrolyte for the miniaturized batteries serving as energy source, and for an electrochromic display system. An illustrative practical embodiment involves housing within a ceramic multi-layer structure a battery with positive electrode and negative electrode for a quartz driving circuit and an electrochromic (ECD) display controlled by an microprocessor. For the flow of current through the ECD there is used a secondary element formed of a WO.sub.3 electrode and a Na-tungstenate electrode as the counter electrode, the WO.sub.3 segments assuming a blue color due to diffusion of Na.sup.+ ions.