Refractory grade silicon carbides

Abrasive and refractory grade silicon carbide is produced industrially according to the following reaction... 

Abrasive and refractory grade silicon carbide is produced industrially by the car-bothermal reduction of silica, according to the reaction in Eq. (3), from high-purity quartz sand (99.5% Si02) and petroleum coke, in electrically heated resistance furnaces (Acheson furnace) [47]. The reaction is strongly endothermic the heat of formation is 618 kj mol SiC, corresponding to 4.28 kWh kg SiC. 

Ceramic catalytic unit, 10 40 Ceramic composites systems, 5 552-554 Ceramic decoration, use of gold in, 12 693 Ceramic ferrites, 11 59 Ceramic fibers, 24 614, 618 refractory, 13 388 silicon carbide, 13 386 Ceramic-grade fluorspar, 4 579, 580 analysis, 4 577t Ceramic, high temperature... 

For applications that require a particularly high grade of silicon carbide, such as industrial ceramics, the refractory industry, and ceramic-bound abrasives, the granular product must be washed with alkali or acid to remove adhering traces of elemental silicon, metals, metal compounds, graphite, dust, and silica. 

Silicon carbide (Carborundum) Norway, USA, Netherlands, Ukraine, Brazil, Japan 400,000 Black grade (99%) 1300-1500 Refractory grade (98 wt.%) 1800-2200 Refractory grade (95 wt.%) 1600-1900... 

Crystar. Tradename. A form of RECRYSTALLISED SILICON CARBIDE (q.v.) in which SiC and electronic grade Si react at over 2300 °C, and the grains recrystallize to form a continuous network of SiC. Crystar is used to produce thermal shock resistant kiln furniture as well as tubes and other refractory shapes. (Norton Co, USA). C-Scan Acoustic Microscopy, C SAM. Focussed transducers from 10 to 100 MHz are coupled to the test piece in a water-immersion tank so that the test-piece is located at the desired depth below the test-piece surface. (The reflections from that surface itself are cut out electronically). Scanning the transducer over the surface produces an image of internal flaws at that depth in the specimen. 

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