Ceramic powder processing technology

On the other hand, improvements in ceramic powder processing technology, the routine preparation of high-purity ceramics of nanometre scale, and the new techniques for the processing of these powders such as HIP, SPS, microwave furnace, etc., will be the driving forces for a very active study on nanoceramics in the near future, probably opening up new phenomena and new applications. 

Ceramic powder processing technology is discussed in the Tao Shuo [9]. This text describes how kaolin raw materials had to be foimd and ground to the desirable size distribution. After grinding, the earth was washed and purified. This was done by mixing it with water in a large... 

Microwave-assisted hydrothermal synthesis is a novel powder processing technology for the production of a variety of ceramic oxides and metal powders under closed-system conditions. Komameni et al. developed this hydrothermal process into which microwaves are introduced. " This closed-system technology not... 

Although the use of alumina as implants can be traced back to the 1930s as described by Hulbert et al (1) (Table 5.1), the extensive use of alumina since the 1980s has depended on new powder processing technology enabling grain size reduction of the sintered ceramics from 10 micrometers... 

Fabrication technologies for ah electronic ceramic materials have the same basic process steps, regardless of the appHcation powder preparation, powder processing, green forming, and densiftcation. 

Vapor—vapor reactions (14,16,17) are responsible for the majority of ceramic powders produced by vapor-phase synthesis. This process iavolves heating two or more vapor species which react to form the desired product powder. Reactant gases can be heated ia a resistance furnace, ia a glow discharge plasma at reduced pressure, or by a laser beam. Titania [13463-67-7] Ti02, siUca, siUcon carbide, and siUcon nitride, Si N, are among some of the technologically important ceramic powders produced by vapor—vapor reactions. 

Ceramic pigments, 7 345-354 19 404 Ceramic-polymer composites ferroelectric, 11 100-101 sol-gel technology in, 23 80-81 Ceramic powders, 1 704 Ceramic processes, chemical-based, 23 53-54... 

Kim Y. S., 1976, Effects of powder characteristics, in F. F. Y. Wang (Ed.), Treatise of Materials Science and Technology, Vol. 9 Ceramic Fabrication Processes, Academic Press, New York. 

Contrary to the above mentioned technologies, which are based on arc plasma furnaces, a radiofrequency (RF) plasma system can process fine powders without granulation in a continuous operation. This possibility, together with the advantageous features of the thermal plasmas mentioned above, offer great perspectives for the synthesis of special ceramic powders such as spinel ferrites [5]. The RF plasma treatment produces nanosized metal and/or oxide powders depending on the parameters of processing. In this paper application of an RF thermal plasma system for the treat-... 

This broad success of the method is due to its ability to form pure and homogeneous products at very low temperatures.5 Thus, the sol-gel technology is replacing the millennia old ceramic fabrication processes in which powders are shaped into objects and subsequently densified at temperatures close to their liquidus. This allowed a transformation of ceramics and glasses from stone age materials to space age materials . 

In relatively recent years the term colloidal processing has been coined to describe processing technologies in which the colloidal properties of ceramic powders are exploited. J.A. Lewis [6] comprehensively reviews colloidal processing and its potential. 

These developments have only been possible because of a continuing improvement in understanding of the basic solid state science of the ceramic dielectrics, of the electrode metals and of the interaction between the two, and particularly of the technologies of ceramic powder production and the MLCC fabrication processes. 

Carbide powder is manufaetured by carburization of the metal, metal oxide or metal hydride with nuclear-pure graphite at ca. 2000°C. Carbide powder pellets (see Section 5.5.5.1.5) or beads up to 0.6 mm in diameter are formed and sintered using ceramic process technology. Reaction sintering is commonly used for the manufacture of uranium earbide fuel beads, in whieh uranium oxide and carbon are first mixed then annealed to form the carbide and then are sintered to 90 to 95% of the theoretical density. An... 

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