Sm2Fe17N2.9compound powders were prepared from parent alloys of Sm2Fe17which were made by both the arc‐melting and rapid solidification processes. The cast Sm2Fe17contained mixed phases of SmFe3and &agr;‐Fe, and correspondingly formed less Sm2Fe17Nxwith a rather large amount of residual &agr;‐Fe after nitrogenation. The melt‐spun Sm2Fe17compound, however, was single phase and exhibited a negligible amount of residual &agr;‐Fe after nitrogenation. The residual amount of free iron was found to increase as a function of milling time and impede the development of promising permanent magnetic properties. The melt‐spun Sm2Fe17Nxcompound powders exhibited a coercivity valueiHcof 5 kOe, which is double that of the as‐cast Sm2Fe17Nxpowders and a high remanence,Br=60 emu/g. The average magnetic moment of Fe atoms in the crystal is estimated to be 2.29 &mgr;Band the Fe atom in the 6csite shows the highest magnetic moment of 2.65 &mgr;B. The expansion in thec‐axial direction of the nitrogenated crystal was found to be mainly due to extension of Sm(6c)‐Fe(6c) and Fe(18f)‐Fe(18f) distances.