METHOD OF PROCESSING OF GRINDING WASTE OF MANUFACTURE OF PERMANENT MAGNETS Russian patent published in 1998 - IPC

FIELD: processing of grinding waste of manufacture of permanent magnets with use of rare-earth metals. SUBSTANCE: proposed method of processing of grinding waste of manufacture of permanent magnets for their reuse in production of Nd-Fe-B magnets includes operations of drying of grinding waste, its oxidation at 550-650 C, magnetic separation of mixture of oxides and their subsequent fluorination by elementary fluorine at temperature 200-350 C. Obtained mixture of fluorides is reduced by outside-furnace method with production of alloying compositions and magnetic alloys. Method ensures 90-95% extraction of needed elements with simultaneous fine cleaning from carbon, boron and silicon. Key alloying elements such as terbium, dysprosium, titanium, cobalt and others are transferred in this case from grinding waste to ingots of alloys and alloying compositions so that there will be no need for their additional injection. EFFECT: improved efficiency of method. 3 cl