PROCESS FOR OBTAINING SILICON NITRIDE AND SILICON CARBIDE

摘要

TO MANUFACTURE BARBES OF SILICON NITRIDE AND SILICON CARBIDE, A CEREAL BALL IS SUBJECTED WITH ACID AND CALCINE, THEN FIRST HEATED IN A NITROGEN ATMOSPHERE, AFTER WHICH THE SILICON NITRIDE BARBES ARE RECOVERED. THEN WE CARRY IT TO A HIGHER TEMPERATURE IN A NON-OXIDIZING ATMOSPHERE, AFTER WHICH THE SILICON CARBIDE BARBES ARE REMOVED, AN ADDITION OF SECONDARY FEED MATERIAL WHICH HAD TAKEN AFTER THE REMOVAL OF THE NITRIDE BARBES. 'FEEDING AGAIN CONSISTING OF BALL PRE-TREATED WITH ACID AND CALCINATED OR FLAKED OF A MIXTURE, WITH AN ORGANIC BINDER, OF SILICON, SILICON NITRIDE AND OF ANOTHER MATERIAL CONTAINING SILICON. THE EXTRACTION OF NITRIDE AND CARBIDE BARBES IS PERFORMED BY TREATMENT, IN EACH CASE, WITH A MIXTURE OF WATER AND A HYDROPHOBIC ORGANIC LIQUID SUCH AS KEROSENE, WHICH WE ALLOW TO SHARE. THE FINAL CARBIDE RESIDUE CAN BE BURNED TO REMOVE CARBON AND GRINDED TO RECOVER SILICON CARBIDE POWDER.