PROCEDURE FOR SIMULTANEOUS PRODUCTION OF SEVERAL FACETED VALUABLE STONES OF SYNTHETIC SILICON CARBIDE - MOISSANITE

摘要

FIELD: metallurgy.;SUBSTANCE: procedure consists in simultaneous growth of multitude of work pieces of moissanite crystals in cellular mould of forming graphite, in dividing them to separate crystals, in faceting, grinding and in polishing. Before faceting, grinding and polishing work pieces are first glued on a mandrel, then they are re-glued on a back side. Moissanite is polished on a ceramic polisher rotating at rate from 200 to 300 rpm with utilisation of diamond powder (spray) with dimension of a grain from 0.125 to 0.45 mcm, facilitating depth of grooves less, than length of light wave of a visible part of spectre. Also, cut and chipped edges of the work piece with defects not suitable for faceting, are crumbled and returned to a stage of growth. Grinding paste with size of a grain 0.25 mcm can be used for grinding.;EFFECT: increased quality of crystals, increased efficiency due to elimination of cutting operation; reduced expenditures for production and losses of material at cutting during work piece growth.;2 cl, 3 ex