METHOD OF PRODUCTION OF ALLOY ON BASE OF TRANSITION AND RARE-EARTH ELEMENTS AND DEVICE FOR REALIZATION OF THIS METHOD Russian patent published in 2003 - IPC

FIELD: metallurgy; methods of metallothermic production of alloys on base of transition and rare-earth elements with alloying additives. SUBSTANCE: proposed method consists in forming upper layer of charge from oxide of transition element and reductant, mainly aluminum and lower layer from rare- earth elements followed by layer-by-layer loading of charge into reaction reservoir and isolation of upper layer of charge from lower one. Metallothermic reduction and separation of metallic and slag phases are performed only in upper layer of charge; after separation of phases isolation between upper and lower layer is partially disturbed; slag phase is separated before interaction of metallic phase with rare-earth elements and crystallization of alloy. Mass ratio of upper and lower layers of charge is no less than 3.05. Used as rare-earth elements are cerium, lanthanum, neodymium, praseodymium or their alloy. Upper layer of charge may additionally contain transition element, that is iron, nickel, cobalt and lower layer may contain alloying additive in form of calcium, aluminum, silicon, copper and boron. Separation of metallic and slag phases is continued for 3-10 s. Device proposed for realization of this method is made in form of crucible whose bottom has mass equal to 0.05-0.20 of mass of metallic phase obtained after reduction; device has tapping channels whose diameter D is found from the following relationship: D = 1^0,5•k₁, where l is thickness of bottom and k₁ is empirical coefficient equal to 0,64-1,04(m)^0,5; partition is made from low-melting or highly combustible material. Number of tapping channels N is found from the following relationship: N = M•k₂, where M is mass of metallic phase; k₂ is empirical coefficient and k₂≥0,004kg^-1. Crucible bottom may be detachable. Housing of crucible and metal receptacle may be manufactured from oxide or fluoride ceramics, from metal or graphite. In the last case, crucible bottom is connected with housing and metal receptacle by means of heat-insulating members, one or more. Extraction of rare-earth elements reaches practically 100%. EFFECT: enhanced efficiency; extended range of concentration of rare-earth and alloying elements. 17 cl, 2 dwg, 5 ex