摘要:
A sealing method and sealed assemblies incorporating novel devitrifiable sealing frits based on thermally crystallizable alkaline earth aluminosilicate glasses, are disclosed. The frits exhibit improved compatibility with refractory composites employed for the fabrication of high temperature fiber-reinforced glass-ceramic assemblies and can be cured at temperatures below those needed to cure prior art sealing compositions to provide strong seals wherein refractory crystal phases selected from the group consisting of anorthite (CaO.Al.sub.2 O.sub.3.2SiO.sub.2), celsian (BaO.Al.sub.2 O.sub.3.2SiO.sub.2), and sanidine, orthoclase or other potash feldspar (K.sub.2 O.Al.sub.2 O.sub.3.6SiO.sub.2) polymorphs constitute the principal phases.
摘要:
This invention relates to the production of laminated structures consisting essentially of a light weight interior member prepared from a glass, glass-ceramic, or ceramic, an exterior member prepared from a glass, glass-ceramic, or ceramic, and a bonding member prepared from a glass, glass-ceramic, or ceramic. The light weight interior member may be composed of a porous body, a corrugated body, or a honeycomb body. In a preferred embodiment, at least one of said members is reinforced through the entrainment of ceramic fibers and/ or whiskers. In the most preferred embodiment, each exterior and interior member is reinforced through the entrainment of ceramic fibers and/or whiskers and the bonding member is reinforced through the entrainment of ceramic whiskers.
摘要:
The present invention is directed to the production of SiC whisker- and/or fiber-reinforced, internally-nucleated glass-ceramic matrix composite articles consisting essentially of 0.5-60% by weight SiC whiskers and/or 15-70% by volume ceramic fibers substantially uniformly distributed in a glass-ceramic matrix consisting essentially, in weight percent on the oxide basis, of 16-20%, CaO, 38.5-46% Al.sub.2 O.sub.3, 35-42% SiO.sub.2, and up to 10% total of at least one nucleating agent in the indicated proportion selected from the group consisting of 0.1-3% Cr.sub.2 O.sub.3, 0.25-3% HfO.sub.2, 2-5% MoO.sub.3, 0.25-3% Nb.sub.2 O.sub.5, 0.25-3% Ta.sub.2 O.sub.5, 0.25-3% WO.sub.3, and 1-10% ZrO.sub.2, wherein Al.sub.2 O.sub.3 is present in an amount which is at least 5 mole percent and up to 50 mole percent in excess of that present in stoichiometric triclinic anorthite, and wherein the predominant crystal phases in the glass-ceramic are triclinic anorthite and mullite and/or .alpha.-Al.sub.2 O.sub.3. Up to 1.5% As.sub.2 O.sub.3 may advantageously be included in the composition.
摘要:
A silicon carbide fiber reinforced barium modified magnesium aluminosilicate matrix composite is described having high strength and thermal stability at temperature in excess of 1200.degree. C. The matrix material contains about 5% to about 14% magnesium oxide and about 5% to about 25% barium oxide. While any suitable ratios of fiber to matrix can be used, the composite for most applications for example, in the heat engine area, will contain approximately 20% to 50% by volume silicon carbide fibers.
摘要:
This invention is directed to the production of glass-ceramic bodies exhibiting high strength and capable of being used at temperatures of 1300.degree. C. and higher. Barium osumilite constitutes the predominant crystal phase and the inventive bodies have overall compositions consisting essentially, in weight percent, of:______________________________________ SiO.sub.2 51-68 Al.sub.2 O.sub.3 17.5-30 MgO 5-12 BaO 3.5-15 Si 0-1 Nb.sub.2 O.sub.5 0-20 Ta.sub.2 O.sub.5 0-10 TiO.sub.2 0-12 ZrO.sub.2 0-6 ______________________________________ The bodies can be utilized in monolith form and are very useful as matrices for fiber reinforced structures suitable for high temperature applications.
摘要:
There is disclosed a method of producing a slurry composed of ion-exchanged, synthetic mica crystals dispersed in a polar liquid. The method comprises providing a synthetic, lithium and/or sodium, water-swelling body of selected crystal type, and dispersing the mica body in the polar liquid while simultaneously effecting an exchange of larger cations from a contacting source with lithium and/or sodium ions from the mica crystals. The synthetic mica body may be vigorously mixed in a dilute solution of the exchangeable ion source. Alternatively, the mica body may be disintegrated in a mixer, the exchangeable ion source added to form a paste and more liquid added to dilute the paste.
摘要:
A heat exchanger 10 includes a conduit 12 for conveying cooling fluid relative to a body to be cooled. A heat transfer arrangement 62 is arranged in communication with an interior of the conduit 12, the heat transfer arrangement 62 and the conduit 12 together defining an assembly that is mountable adjacent the body to be cooled, convective heat exchange occurring, in use, due to movement of the cooling fluid relative to the body and to the heat transfer arrangement 62 of the assembly and radiant heat exchange occurring between the body and at least part of the heat transfer arrangement 62 of the assembly.
摘要:
A heat exchanger 10 includes a conduit 12 for conveying cooling fluid relative to a body to be cooled. A heat transfer arrangement 62 is arranged in communication with an interior of the conduit 12, the heat transfer arrangement 62 and the conduit 12 together defining an assembly that is mountable adjacent the body to be cooled, convective heat exchange occurring, in use, due to movement of the cooling fluid relative to the body and to the heat transfer arrangement 62 of the assembly and radiant heat exchange occurring between the body and at least part of the heat transfer arrangement 62 of the assembly.
摘要:
A heat exchanger 10 includes a conduit 12 for conveying cooling fluid relative to a body to be cooled. A heat transfer arrangement 62 is arranged in communication with an interior of the conduit 12, the heat transfer arrangement 62 and the conduit 12 together defining an assembly that is mountable adjacent the body to be cooled, convective heat exchange occurring, in use, due to movement of the cooling fluid relative to the body and the heat transfer arrangement 62 of the assembly and radiant heat exchange occurring between the body and at least part of the heat transfer arrangement 62 of the assembly.
摘要:
A system (10) for controlling an industrial plant (12) comprises automatic control equipment (14) comprising a plurality of measurement sensors (16) for sensing predetermined variables associated with components of the industrial plant (12). The sensors (16) generate measured data relating to operation of the components of the industrial plant (12). A database (20) contains operational data, including observational data, regarding the industrial plant (12). A processor (18) is in communication with the automatic control equipment (14) and the database (20) for receiving the measured data from the sensors (16) of the automatic control equipment (14) and the operational data from the database (20). The processor (18) manipulates the measured and operational data to provide an evolving description of a process condition of each component over time, along with output information relating to operational control of the industrial plant (12) and for updating the database (20).