Shaping techniques, silicon carbides

The other method of developing fine, spherical particles is through the use of plasma techniques which may involve a phjrsical phenomenon or a chemical reaction [105]. In the former case, a simple spherodizing process takes place when irregular shaped powder is introduced into the plasma which melts it and then vaporizes it to form uniform spheres. When a chemical reaction is involved, the reactants in the solid or gaseous form in contact with the plasma are allowed to react in the vapor phase and the products are allowed to condense as deposits of tine powder on the cooler regions of tire chamber after leaving the plasma. Colloidal spheres of alumimun, copper, aluminum nitride and silicon carbide are made in this way. 

Two shaping techniques, turning on a lathe and cutting with a silicon carbide saw, were found to be acceptable provided samples are subsequently etched. 

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