Abstract:
The invention relates to a module element comprising a high-temperature resistant base, said high-temperature resistant base having at least one metal or ceramic bottom that has at least one through-passage for introducing a ceramic capillary membrane, and at least one potting that is formed as a sufficiently gas-tight and high-temperature resistant connection between the metal or ceramic bottom and the at least one ceramic capillary membrane. The at least one through-opening of the at least one metal or ceramic bottom has an enlarged portion on at least one side of the metal or ceramic bottom for accommodating the sufficiently gas-tight and high-temperature resistant connection.
Abstract:
Bei Bauteilen mit einem Keramikkörper, der an mindestens einer Stelle seiner Oberfläche mit einer Metallisierung bedeckt ist, können Probleme mit der Haltbarkeit und der Haftfestigkeit der metallischen Beschichtungen auftreten. Erfindungsgemäß wird deshalb vorgeschlagen, dass der Werkstoff an der Oberfläche des Keramikkörpers an den Stellen der Metallisierung vollflächig oder teilflächig durch chemische oder physikalische Vorgänge chemisch und/oder kristallografisch und/oder physikalisch mit oder ohne Zugabe geeigneter Reaktionsstoffe verändert ist und mindestens eine mit dem Keramikkörper verbundene dichte oder poröse Schicht mit einer gleichen oder ungleichen Dicke von mindestens 0,001 Nanometern bildet, die aus mindestens einem homogenen oder heterogenen neuen Werkstoff besteht.
Abstract:
The invention is directed to highly crystalline, frit sintered glass ceramic compositions having a coefficient of thermal expansion in the range of 85 115 x 10 -7 °C. The primary crystal phases of the glass ceramics of the invention possess a cyclosilicate structure. The glass ceramic of the invention are useful as metal to metal, metal to ceramic and ceramic to ceramic sealing agents, and also as high performance coating for metals and ceramics. In their broadest composition the glass ceramic contain, in weight percent, 30-55% SiO 2 , 5-40% CaO, 0-50% BaO, 0.1-10% Al 2 O 3 , and 0 40% SrO, wherein the sum of CaO + BaO + SrO is in the range of 35-65 wt. %. Optionally, the glass ceramic compositions may contain at least one from the group of >0 15 wt. % MgO and >0 10 wt. % ZnO. Also optionally, the glass ceramic compositions may contain >0 10 wt. % of at least one transition metal or rare earth metal oxide.
Abstract:
An aluminum-boron-carbon (ABC) ceramic-metal composite bonded to a metal or metal-ceramic composite other than ABC composite is made by forming a porous body comprised of particulates being comprised of a boron-carbon compound that has a particulate layer of titanium diboride powder on the surface of the porous body. The porous body is infiltrated with aluminum or alloy thereof resulting in the simultaneous infiltration of the TiB 2 layer, where the layer has an aluminum metal content that is at least about 10 percentage points greater by volume than the (ABC) composite. The ABC composite is then fused to a metal or metal-ceramic body through the infiltrated layer of titanium diboride, wherein the metal-ceramic body is a composite other than an aluminum-boron-carbon composite.
Abstract:
The invention relates to a joint between a metal part (1) and a ceramic part (7) which is made from a ceramic material that is based on SiC and/or C. The inventive joint is characterised in that it comprises a stacked structure consisting of the following elements which are assembled in pairs, in the following order, by means of brazing, namely: the metal part (1), a first spacer (3), a second spacer (5), and the ceramic part (7). According to the invention, the second spacer (5) is made from another ceramic material which is less chemically reactive with metals than SiC or C and which has a lower expansion coefficient than that of the material forming the metal part (1). Moreover, the first spacer (3) is metal and can deform in order to compensate for the expansion differential between the metal part (1) and the second spacer (5). The invention also relates to the use of said joint in a turbomachine.
Abstract:
Process for producing a joint between a ceramic part and a part made of metal, with a sealing material consisting, for 100% of its weight, of 10 wt% to 90 wt% of a glass or a glass mixture (G); and 10 wt% to 90 wt% of at least one ceramic (C), said process comprising the following successive steps: either - a step (a) of preparing a powder blend (B) consisting, of a glass powder (G) and a ceramic powder (C); - a step (b) of pressing a preform, obtained from the powder blend (B); - a step (c) of densifying the preform; - a step (d) of positioning the elements of the ceramic joint that are complementary to the preform; and - a step (e) of positional heat treatment of the seal prepared in step (d), or - a step (b) of pressing a preform of a powder of at least one ceramic (C); - a step (c) of partially densifying the preform; - a step (d) of positioning the elements of the ceramic/metal joint that are complementary to the preform; and - a step (e') of heat treating the preform so as to cause the glass to infiltrate into the porosity of said preform. Sealing material employed and ceramic/metal joint assembly that includes said sealing material.
Abstract:
Die Lampe verwendet ein Abdichtungssystem mit einem keramischen Stützelement (17) kurzer Länge LA zusammen mit einem W-Nb- Durchführungsteil (18,19,20) und einem speziell angepassten Glaslot (21), das auf einem Al 2 O 3 -Selten Erd-Oxid-System basiert. Dabei ist der W-Teil über eine Länge LW von 1mm in das Stützteil aufgenommen, und das Aspektverhältnis LW/DUW, gebildet aus der Länge LW und dem Durchmesser DUW des W-Teils, ist mindestens 10.