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Metal maximum operating temperatur

The change of capacitance in relation to the temperature is very small and a linear function of the substrate temperature. Unlike the change in metal film capacitors it is completely reversible. The maximum operating temperature of the capacitor chip (more than 200°) is determined by its aluminum gate. For encapsulated systems the bond contacts and the material of the package will determine the upper temperature limit. [Pg.234]

Porous metals have long been commercially available for particulate filtration. They have been used in some cases as microfiltration membranes that can withstand harsh environments, or as porous supports for dynamic membranes. Stainless steel is by far the most widely used porous metal membrane. Other materials include silver, nickel. Monel, Hastelloy and Inconel. Their recommended maximum operating temperatures range from 200 to 650°C. Elepending on the pore diameter which varies from 0.2 to 5 microns, the water permeability of these symmetric membranes can exceed 3000 L/h-m -bar and is similar to that obtained with asymmetric ceramic microfiltration membranes. Due to the relatively high costs of these membranes, their use for microfiltration has not been widespread. [Pg.67]

On the other hand, following the development of hybrid combustor configurations that prevent operation of the catalyst module at temperatures above 900-1000 °C, the major drawback of metallic monoliths, namely the limited maximum operating temperature, has been overcome. Accordingly, honeycombs made of metal foils have been adopted in GT catalytic combustors in view of their excellent thermal shock resistance and thermal conductivity properties [9]. In addition, metallic substrates are a promising option for the fabrication of microcombustors. [Pg.376]

Most fiber-matrix composites (FMCs) are named according to the type of matrix involved. Metal-matrix composites (MMCs), ceramic-matrix composites (CMCs), and polymer-matrix composites (PMCs) have completely different structures and completely different applications. Oftentimes the temperatnre at which the composite mnst operate dictates which type of matrix material is to be nsed. The maximum operating temperatures of the three types of FMCs are listed in Table 1.27. [Pg.103]

Solid catalysts can be used at elevated temperatures, though their acidities are much weaker than those of liquid ones. From this point of view, solid superacids based on Lewis acids and liquid superacids discussed in Sections II—1V are not sufficiently stable Nafion-H is also unsatisfactory, its maximum operating temperature being below 200°C. A new type of the sulfate-supported metal oxides is more stable because of preparatory heat treatment at high temperatures, but elimination of the sulfate is sometimes observed during reaction, thus it is hoped to synthesize superacids with the system of metal oxides. Another type of superacid, tungsten or molybdenum oxide supported on zirconia, has been prepared by a new preparation method, and its stability is satisfactory so far. It is hoped that the preparation method will be extensively applied to other metal oxides for new solid superacids. [Pg.206]

Metal monoliths have interesting properties, such as high tolerance for mechanical stress and vibrations and high thermal conductivity. Moreover, the cell walls may be thinner as compared to their ceramic counterparts. However, the maximum operating temperature of metal monoliths is not as high as for vanous ceramics. This is not a problem for certain combustor designs that limit the temperature in (part of) the catalyst... [Pg.166]

The disadvantage of metallic monoliths is that their maximum operating temperatures are substantially below the 1300 °C combustor outlet temperature required for current gas turbines. They can therefore only be used in combustor designs that limit the catalyst wall temperature in some way, such as the hybrid combustors described above in Section 3.4. [Pg.191]

Several different materials have been studied. Metallic monoliths have been used extensively since their first application for automobile converters. They allow very thin walls and have a very high thermal conductivity. However, their thermal expansion gives rise to some problems when looking at the coating and stability of the washcoat on the metallic surface, compared with the ceramic monolith. Furthermore, their maximum operation temperature is limited to 1200-1400 C, cf. Table 1. Probably, the maximum temperature is somewhat lower for long-time exposure. However, several ceramic monoliths that can stand higher thermal conditions have been developed, as reported in Table 1. [Pg.187]

In power compensated DSC the small size of the individual sample and reference holders makes for rapid response. The temperature sensors are platinum (Pt) resistive elements. The individual furnaces are made of Pt/Rh alloy. It is important that the thermal characteristics of the sample and reference assemblies be matched precisely. The maximum operating temperature is limited to about 750 °C. High temperature DSC measurements (750-1600°C) are made by heat flux instruments using thermocouples of Pt and Pt/Rh alloys. The thermocouples often incorporate a plate to support the crucible. The use of precious metal thermocouples is at the expense of a small signal strength. Both chromel/alumel and chromel/constantan are used in heat flux DSC equipment for measurements at temperatures to about 750 °C. Multiple thermocouple assemblies offer the possibility of an increased sensitivity - recently a 20-junction Au/Au-Pd thermocouple assembly has been developed. Thermocouples of W and W/Re are used in DTA equipment for measurements above 1600°C. The operating temperature is the predominant feature which determines the design and the materials used in the con-... [Pg.69]

PBT gears have extremely smooth surfaces and have a maximum operating temperature of 150 for unfilled and 170 "C for glass reinforced grades. PBT works well against polyacetals and other plastics as well as against metal and is utilised in... [Pg.164]

Green to bluish black, iridescent crystals. Soluble in fused alkali hydroxides. Abrasives best suited for grinding low-tensile-strength materials such as cast iron, brass, bronze, marble, concrete, stone and glass, optica structural, and wear-resistant components. Corroded by molten metals such as Na, Mg, Al, Zn, Fe, Sn, Rb, and Bi. Resistant to oxidation in air up to 1650°C. Maximum operating temperature of 2000°C in reducing or inert atmosphere. [Pg.655]

Golden brown crystals, soluble inHF-HNOj mixture. Crucible container for melting ZrO and similar oxides with high melting point. Corrosion resistant to molten metals such as Ta and Re. Readily corroded by liquid metals such as Nb, Mo, and Sn. Burning occurs in pure oxygen above 800°C. Severe oxidation in air above 1100-1400°C. Maximum operating temperature of 3760°C in helium... [Pg.656]

Gray crystals. Superconducting at 1.1 K. Soluble inHNOjand aqua regia. Resistant to oxidation in air up to 450°C. Maximum operating temperature 3000°C in helium. Crucible container for handling molten metals such as Na, Bi, Zn, Pb, Sn, Bi, Rb, and Cd. Corroded by liquid metals Mg,... [Pg.656]

Dark gray brittle solid, soluble nHF solutions containing nitrate or peroxide ions. UC-nuclear power reactor, crucible ontainer for handling molten metals such as Bi, Cd, Pb, Sn, lb, and molten zirconia ZrO. Corroded by liquid metals Mg, Al, Si, V, Nb, Ta, Cr, Mo, Mn, Fe )o, Ni, and Zn. In air oxidizes rapidly above 500°C. Maximum operating temperature of 2350°C n helium... [Pg.657]

TableF.l. Maximum operating temperature ("C) of metals for handling liquid metals under inert atmosphere (A = Attacked)... TableF.l. Maximum operating temperature ("C) of metals for handling liquid metals under inert atmosphere (A = Attacked)...
A commercially acceptable pyrolysis coil design is constrained by the limitations in available metallurgy. For any selected material, there exists a maximum operating temperature beyond which tube life is sharply reduced. This limitation in metal temperature must be considered in setting the coil design. [Pg.363]

Gears mannfactnred from fiber-reinforced polybutylene terephthalate have an extremely smooth snrface and high maximum operating temperature up to 170°C. This composite is superior to polyacetal or metals and is often used in the manufacture of engine housings. [Pg.187]

The carbon-fiber/polymer composites reviewed in the previous section have excellent mechanical properties but limited temperature resistance. Maximum operating temperature is presently 370°C (Table 9.2). These composites cannot meet the increasingly exacting requirements of many aerospace applications which call for a material with low density, excellent thermal-shock resistance, high strength, and with temperature resistance as high or higher than that of refractory metals or ceramics. These requirements are met by the so-called carbon-carbon materials. [Pg.209]

Care has to be taken that the precious metal water-gas shift catalyst does not overheat during regeneration treatment in an oxidative atmosphere, because this impairs the dispersion of the active metals [314]. It is difficult to judge the actual temperature at the catalyst surface and thus the overall temperature should be kept well below the maximum operating temperature of the catalyst during regeneration. [Pg.116]

Many alternatives exist and the choice between thermoplastic and thermosetting resins depends on the expected lifetime and maximum operating temperature. Styrene-butadiene block copolymers and acrylic resins can be used to produce low-end adhesives with an acceptable stability up to 100°C, whereas epoxy and silicone thermosets are preferred for their robustness at 150-200°C. In the most severe environments, poly(imide-siloxanes) and polyimides can sustain medium-term exposures to 250 and 300°C, respectively. Various conductive fillers are cited in the literature, including noble metals such as gold or silver, and low-cost metals such as copper, nickel, chromium, and soft solders. [Pg.432]

The maximum operating temperature for each of the two access systems will be governed mainly by the performance of the non-metallic components of the pressure sealing devices utilized within the various parts of the fitting assemblies and probes. [Pg.269]


See other pages where Metal maximum operating temperatur is mentioned: [Pg.341]    [Pg.436]    [Pg.310]    [Pg.383]    [Pg.17]    [Pg.341]    [Pg.374]    [Pg.183]    [Pg.121]    [Pg.13]    [Pg.27]    [Pg.493]    [Pg.24]    [Pg.184]    [Pg.88]    [Pg.183]    [Pg.97]    [Pg.303]    [Pg.457]    [Pg.463]    [Pg.731]    [Pg.457]    [Pg.463]    [Pg.463]    [Pg.465]    [Pg.385]    [Pg.214]   
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