Research of Dysprosium, Terbium and Neodymium Oxides Fluoration

Abstract

Production of high energy permanent magnets (HEPM) on the basis of rare-earth metals is one of leading knowledge intensive branches of world industry. Raw materials for production of magnets are magnetic alloys. In order to increase magnetic features scientists implement the additives of certain metals and their compounds, such as dysprosium and terbium additives in substantial amounts – up to 7-8 %.Within the framework of a ladle fluoride technology of HEPM manufacturing on the basis of a system Nd-Fe-B, developed by authors, scientists implement the additives of dysprosium and terbium fluoride, by virtue where of there was conducted a research on fluoration kinetics of corresponding oxides by elemental fluorine. The present article quotes results of such research and defines main kinetic parameters of examined processes – diffusion coefficient, kinetic constant and activation energy. Aiming to cost reduction of fluoride manufacture ammonium fluoride was used as a fluorinating agent by the example of fluoration of neodymium oxide.