Requirements to purity and quality of rare earth metals and alloys with magnetic and magnetostriction properties

The data on influence of doping components and impurities upon magnetic properties, corrosion resistivity and economical charactristics of alloys for permanent magnets of REM-iron-boron type are generalized. It is shown that for permanent magnets not pure REM may be used but the components of complex composition applying the individual approach to impurities and accounting for specific requirements to different types of magnets. The results of research in the field of preparation of magnetostriction alloys of REM-iron alloys showed the necessity in high purification of the REM used to this purpose from refractory oxides and oxygen