Influence of milling conditions on magnetic properties of Nd(Fe,Mo)(12)N-xcompounds

Ball milling conditions were examined for the preparation of fine Nd(Fe,Mo) (12)N-x particles. The milling process with high ratio of ball to powder pr oduced Nd(Fe,Mo)(12)N-x particles with low iH(c) and 4 pi I-r. The decrease in 4 pi I-r and iH(c) was attributed to population of alpha-Fe and particl e aggregates that were formed during the milling. The addition of process c ontrol agents (PCA, e.g. stearic acid) prevented aggregation in the ball mi lling, however, a large amount of alpha-Fe was precipitated during the recr ystallization and an improvement of magnetic properties, as hoped for, did not occur. (C) 1999 Published by Elsevier Science B.V. All rights reserved.