Silicon carbide wetting

Figure 17. Scanning electron micrograph of a silicon carbide wet abrasive paper (grain size P1200).

Although diamond is the abrasive that is used most frequently for ceramics, other abrasives are also used. The basic rule is that their hardness must be greater than the hardness of the material being processed. It is generally best to process aluminum oxide ceramics with diamond abrasives. Silicon carbide wet abrasive papers can be used for graphite, zinc oxide, and silicate ceramics. 

FIGURE 26.8 The friction master curves of the acrylate-hutadiene rubber (ABR) gum mbber on (a) dry glass, (b) dry clean silicon carbide 180, (c) dry silicon carbide dusted with MgO powder, (d) Alumina 180 wetted with distilled water, and (e) wetted with water +5% detergent. 

Shear modulus, 13 498, 26 777 of dry foams, 12 16 of silicon carbide, 22 526t of vitreous silica, 22 430 of wet foams, 12 17-18 Shear plane, polymer colloid, 20 383, 384 Shear pulverization, of polymer blends, 20 326... 

Wear shell specifications, for wet drum ore concentrator, 15 449 Wear surfaces, silicon carbide in, 22 538 Wear testing, 9 713 Weatherability... 

In Table 9.6 we see that the pure silicon carbide surface is basic, although the oxidized silicon carbide surface is acidic like that of silica. With these E and C values Okuyama et al. [21] were able to predict that the silica and oxidized silicon carbide surfaces are best wet by... 

Various electrical and optical properties that have been measured for the wet thermal oxide on silicon carbide are summarised in TABLE 3. In general, no systematic variation of any of the oxide properties has been reported with oxide growth temperature in the range of 1000 to 1250°C. However, oxide grown with a wet process has been shown to have lower oxide charges than oxide grown in dry oxygen. Variations in the measured electrical properties... 

The specimen surface is often prepared before measurement to ensure a reproducible and known surface condition. Metallurgical surface preparation techniques are commonly used, these include wet grinding on silicon carbide abrasive papers, polishing with diamond or alumina media, electropolishing, chemical polishing, pickling or etching. 

A rather different approach has been developed for reaction sintered silicon carbide (RSSC), first developed in the former Soviet Union. In this process a powder preform of mixed graphite and silicon carbide is immersed in a liquid bath of molten silicon. The silicon wets and infiltrates the preform, reacting with the finely-divided graphitic component (carbon black). In the best case, all graphite is reacted and the residual sihcon content is no more than a few percent. The product of the reaction, silicon carbide, firmly bonds the silicon carbide preform powder... 

E. J. Opila, Oxidation Kinetics of Chemically Vapor Deposited Silicon Carbide in Wet Oxygen, i Am. Ceram. Soc., 77(3), 730-736 (1994),... 

Diamond, silicon carbide, titanium carbide, and gallium nitride are materials that do not have wet etch processes, but RIE processes do... 

Abrasive wet cutting, using metal or bakelite abrasive cut-off wheels impregnated with alumina, boron nitride, silicon carbide, or diamond, is most appropriate and gives rise to minimum deformation of the cut surface. Wheels may be distinguished as hard or soft depending on their ability to retain or discard the abrasive particles. In general, the harder (more difficult to cut) materials require softer wheels because these provide a continuous supply of new abrasive particles to the surface (but at the same time wear away more quickly). 

The lumps of silicon carbide obtained when the furnace is dismantled are sorted, broken down, milled, sieved, air-classified and wet chemically purified so as to remove any adhering traces of elemental silicon, metals, metal compounds, graphite, dust, and silica [52-54]. 

Rocher JP, Quenisset JM, Naslain R, Wetting improvement of carbon or silicon carbide by aluminum alloys based on a K2Zrp6 surface treatment Application to composite material casting, J Mater Sci, 24, 2697, 1989. 

Silicon carbide waterproof paper n. Hard, sharp, coated abrasive particularly suited for lacquer, plastics and non-ferrous metals, also for wet sanding primes, undercoats and between coats on wood and metal using water, oil, or other lubricants. See coated abrasive. 

HYDROTHERMAL OXIDATION OF SILICON CARBIDE AND ITS BEARING ON WET WEAR MECHANISMS... 

Hydrothermal Oxidation of Silicon Carbide and its Bearing on Wet Wear Mechanisms... 

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