Monolithic components

Chemical vapor deposition (C VD) is a versatile process suitable for the manufacturing of coatings, powders, fibers, and monolithic components. With CVD, it is possible to produce most metals, many nonmetallic elements such as carbon and silicon as well as a large number of compounds including carbides, nitrides, oxides, intermetallics, and many others. This technology is now an essential factor in the manufacture of semiconductors and other electronic components, in the coating of tools, bearings, and other wear-resistant parts and in many optical, optoelectronic and corrosion applications. The market for CVD products in the U.S. and abroad is expected to reach several billions dollars by the end of the century. 

Coatings and monolithic components of h-BN are usually produced by CVD by the reaction of a boron halide with ammonia. MOCVD and plasma-CVD are also used. The reaction of boron trichloride and ammonia is as follows ... 

The original improvements described above allow us to build up a simple and inexpensive apparatus, which is nevertheless especially suitable for the particular purposes of this paper. Indeed, we limited ourselves to using a few standard monolithic components. 

Figure 1.8. CVD fabricated monolithic components (a) thin-wall Rh thruster chamber [5] and (b) SiC components [42]...

The development of a wrapper includes several tasks. Syntax and semantics of the given interface, the source interface, to be wrapped as well as of the interface required by the client, the target interface, have to be specified. Furthermore, the transformation of the source into the target interface has to be defined. Consequently, a wrapper is not a monolithic component, it is rather a subsystem consisting of several subcomponents [136]. 

The CVD method involves a chemical reaction in a vapor phase which results in deposition of a solid on a heated surface. Various PVD processes such as ion plating, sputtering, molecular beam, evaporation, and epitaxy might be also included in CVD processes [112]. The various CVD methods are powerful processes used for the fabrications of a wide variety of thin-film materials including solar cell materials and semiconductor materials for electronic applications, as well as the manufacture of coatings, powders, fibers, and monolithic components. There are two types of CVD reactors, the differential reactor and the starved reactor, according to the value of the flow rate (F,) defined as... 

The nitridation imder ammonia of the yellowish PAIC compacts leads to the formation at 1000°C of white, crack-free amorphous SiAlON pellets with a linear shrinkage of 20%. After an additional pyrolysis step under flowing nitrogen at 1500°C the amorphous samples convert into microcrystalline pSiAlON monolithic components with a further linear shrinkage of 20%. 

Polymer pyrolysis is also very flexible regarding the type of component that can be obtained fibers, films, membranes, foams, ceramic/ceramic joints, ceramic matrix composites, and monolithic bodies can all be fabricated. The present study has been focused on the formation of monolithic component and thin ceramic films. 

Very complex laser materials for multiple total-reflection active mirrors (TRAM) have also been produced by using ceramic techniques [80-82]. Composite multifunctional monolithic components consisting of the active material and a proper... 

CVD is a versatile process, well adapted to the production of all the refi actory carbides and nitrides not only as coatings but also as powders, bulk/monolithic components, and fibers. It may be defined as the deposition of a solid on a heated surface firom a chemical reaction in the vapor phase. Its advantages are ... 

Reduce the number of protruding fasteners (bolts, rivets) to a reasonable minimum. Preferred welded joints aid shaping of optimal surfaces. Monolithic components are best, if practicable (see Figure 10.14). 

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