Using hydrogen for the production of Fe-Nd-B system permanent magnets

The gas atomized powders of the Fe-TM-Nd-REM-B system have a hydrogen absor ption capacity of the same order as that of a cast alloy of identical chemi cal composition. This paper presents a theoretical explanation of a value o f tetrahedral pores in the lattice of Fe14Nd2B phase. In the volume of thes e pores we selected the polyhedrons. Their distribution explains sorption c apacity, kinetics to sorption and symmetry of distorting a lattice of Fe14N d2B phase during the absorption of hydrogen. We have found that a cyclical hydride processing of the GAP raises the residual magnetic induction of mag netoplasts produced from them. This occurs as a consequence of hydrogen emb rittlement of GAP. Disintegration of powder during production of magnetopla sts brings about such consequences. The GAP (in contrast to powder obtained by mechanical size reduction) have a more pronounced effect of form preser vation during a cyclical hydride processing. (C) 1999 International Associa tion for Hydrogen Energy. Published by Elsevier Science Ltd. All rights res erved.