Ceramic characteristics

The two covalent carbides have low density, low atomic weight, and useful semiconductor properties. They are extremely hard and strong materials which exhibit typical ceramic characteristics. 

They are hard and strong materials and exhibit typical ceramic characteristics. 

Radin, S.R. and Ducheyne, P. (1992) Plasma spraying induced changes of calcium phosphate ceramic characteristics and the effect on in vitro stability. /. Mater. Sci. - Mater. Med., 3, 33-42. 

Homogenization— U02 powder from the conversion process is homogenized in a large, criticality-safe mixer with an orbital-arm screw to achieve uniformity of ceramic characteristics in batches that may exceed 2000 kg. 

As seen above, the atomic structure of interstitial carbides is a mixture of ionic, covalent, and metallic bonding. As a result, the properties of these compounds reflect this structural mix and combine metallic and ceramic characteristics as summarized in Table 3.11. 

Berlincourt D (1981) Piezoelectric ceramics Characteristics and appUcations. J Acoust Soc Am... 

The systems of such type have been developed of all last 10 years. We shall bring some characteristics of one of the last development within the framework of European BRITE project, carried out in LETT This 3D cone-beam tomograph is referred to as EVA Bench or Equipment for Voludensimetry Analysis. It is oriented on NDT of industrial products from ceramics and other composites. One of the main task of this tomograph is achievement of high resolution at study of whole internal volume of researched object. For test sample of the size 10mm spatial resolution in 50mm was obtained [14]. 

It also has potential use in ceramic and glass formulas, as the oxide has a high melting point and imparts shock resistance and low expansion characteristics to glass. 

TechnicalBull on Characteristics ofTyocera Technical Ceramics, Kyocera Corporation, 1988. 

With the exception of glass fiber, asbestos (qv), and the specialty metallic and ceramic fibers, textile fibers are a class of soHd organic polymers distinguishable from other polymers by their physical properties and characteristic geometric dimensions (see Glass Refractory fibers). The physical properties of textile fibers, and indeed of all materials, are a reflection of molecular stmcture and intermolecular organization. The abiUty of certain polymers to form fibers can be traced to several stmctural features at different levels of organization rather than to any one particular molecular property. 

Electromagnetic flow meters ate avadable with various liner and electrode materials. Liner and electrode selection is governed by the corrosion characteristics of the Hquid. Eor corrosive chemicals, fluoropolymer or ceramic liners and noble metal electrodes are commonly used polyurethane or mbber and stainless steel electrodes are often used for abrasive slurries. Some fluids tend to form an insulating coating on the electrodes introducing errors or loss of signal. To overcome this problem, specially shaped electrodes are avadable that extend into the flow stream and tend to self-clean. In another approach, the electrodes are periodically vibrated at ultrasonic frequencies. 

The glass-ceramic phase assemblage, ie, the types of crystals and the proportion of crystals to glass, is responsible for many of the physical and chemical properties, such as thermal and electrical characteristics, chemical durabiUty, elastic modulus, and hardness. In many cases these properties are additive for example, a phase assemblage comprising high and low expansion crystals has a bulk thermal expansion proportional to the amounts of each of these crystals. 

Several manufacturers of ceramic powders are involved in commercializa tion of hydrothermaHy derived powders. In the United States, Cabot (Boyertown, Peimsylvania) has built a small manufacturing plant and is supplying materials to capacitor manufacturers. Other manufacturers include Sakai Chemical and Euji Titanium in Japan. Sakai Chemical is reportedly producing 1 t/d in its demonstration plant. A comparison of the characteristics of commercially available powders is given in Table 2. 

Research and development in the field ate stiU continuing at a fast pace, particularly in the area of absorption and emission characteristics of the polymers. Several reasons account for this interest. First, the intractable polydimethyl silane [30107-43-8] was found to be a precursor to the important ceramic, siUcon carbide (86—89). Secondly, a number of soluble polysdanes were prepared, which allowed these polymers to be studied in detail (90—93). As a result of studies with soluble polymers it became cleat that polysdanes are unusual in their backbone CJ-conjugation, which leads to some very interesting electronic properties. 

The thermal expansivity of Ni—Fe alloys vary from ca 0 at ca 36 wt % Ni (Invar [12683-18-OJ) to ca 13 x 10 / C for Ni. Hence, a number of compositions, which are available commercially, match the thermal expansivities of glasses and ceramics for sealing electron tubes, lamps, and bushings. In addition, the thermal expansion characteristic is utilized ia temperature controls, thermostats, measuriag iastmments, and condensers. 

CH2—CI2—) —(—CF2— CFH—) (39). Ceramic crystals have a higher piezoelectric efficiency. Their high acoustic impedance compared to body tissues necessitates impedance matching layers between the piezoelectric and the tissue. These layers are similar in function to the antireflective coatings on a lens. Polymer piezoelectric materials possess a more favorable impedance relative to body tissues but have poorer performance characteristics. Newer transducer materials are piezoelectric composites containing ceramic crystals embedded in a polymer matrix (see Composite materials, polymer-MATRIX Piezoelectrics). 

Characteristics ofMlumina Powders, Alumina Ceramic Manufacturers Association, New York, 1976, pp. 1—4. 

Plasma processing technologies ate used for surface treatments and coatings for plastics, elastomers, glasses, metals, ceramics, etc. Such treatments provide better wear characteristics, thermal stability, color, controlled electrical properties, lubricity, abrasion resistance, barrier properties, adhesion promotion, wettability, blood compatibility, and controlled light transmissivity. 

The use of porous formers ia the dippiag process, or porous molds prepared from plaster of Paris or uaglazed porcelaia with a surface pore size smaller than the majority of mbber particles, has been widely adopted ia the latex iadustry. With the porous porcelaia formers, the mbber particles are filtered oa the surface of the formers. The mbber latex coagulates because of its high coaceatratioa to form a film of increa sing thickness as more water is absorbed iato the ceramic. Its rate of iacrease diminishes sharply beyoad an optimum period of time, however, depending on the various characteristics of the ceramic. 

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