Silicon Carbide Platelets

Wang, P. S., Malghan, S. G., Hsu, S. M., and Wittberg, T. N., Surface oxidation of silicon carbide platelets as studied by x-ray photoelectron spectroscopy and bremsstrahlung-excited Auger electron spectroscopy. Surf. Interfac. Anal., 18, 159 (1992). 

Dense SiC platelet reinforced silicon carbide composites were recently fabricated [52]. The highest sintered densities of 97-98% TD were achieved with 20% platelet contents using hot molding as the thermoplastic forming technique [53]. 

EKasic W silicon carbide is a dense material with a predominantly coarse-grained bimodal platelet structure. The effectiveness of the coarser microstructure (see Fig. 30) in improving the corrosion resistance has been clearly demonstrated in practical tests on a mechanical seal test rig. Even after 500 h of testing (deionized water, 60°C, 6 bar, hard/hard couples) no Si02 layer was formed on the functional surface. 

EKasic HW silicon carbide, on the other hand, is a dense material with a predominantly coarse-grained, bimodal platelet structure and graphite particles of 40-60 pm in size (see Fig. 31). This new tribological material, which is still in its test phase, should be particularly suitable for mechanical seals and sliding bearings in applications in contact with hot water containing solids. 

I. Wadsworth and R. Stevens, Strengthening and Toughening ofCordierite by the Addition of Silicon Carbide Whiskers, Platelets and Particles, 7. Mat. Sci. 26 6800 808 (1991). 

Silicon carbide was an early approach to the high levels of restenosis caused by BMS. The idea was that interaction between fibrinogen and the stent surface would lead to fibrin deposition, leading to platelet adhesion and thrombus formation thus adding a semiconductor may decrease these electron interactions. [23] Unfortunately the clinical studies of stents coated by amorphous, phosphorous-doped, hydrogen rich silicon carbide showed no difference in restenosis rate when compared to the typical BMS [24]. 

The inks are prepared by mixing an epoxy resin (Epon 826 epoxy resin) with dimethyl methyl phosphonate, nanoclay platelets (Cloisite 30b), silicon carbide whiskers (SI-TUFF SC-050), and milled carbon fibers (Dialead K223HM). Further, an imidazole-based ionic liquid is employed as a latent curing agent (Basionics VS03) (31). 

C. De Johghe, T. Mitchell, W. 1. Moberly-Chan, and R.O. Ritchie, Silicon Carbide Platelet/Sihcon Carbide Composites, Journal American Ceramics Society, 1994. 

SILICON CARBIDE PLATELETS. Single crystals of alpha-phase hexagonal crystal structure. Four size ranges currently are produced —100, H-200 mesh (100-300 /rm in diameter, 5-15 /rm thick) —200, H-325 mesh (50-150 /rm in diameter, 1-10 /rm thick) —325 mesh (5-70 /rm in diameter, 0.5-5 /rm thick) and 00 mesh (3—30 /rm in diameter, 0.5-3 /rm thick). The finest size... 

In addition to reinforcing ceramics, silicon carbide platelets also are used to increase the strength, wear resistance and thermal shock performance of aluminum matrices, and to enhance the properties of polymeric matrices. Because platelets are very free-flowing, they can be processed in the same manner as particulates. 

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