Abstract: Thecrystalstructure and magnetic propertiesof R2 Fe17 xCrx( R= Y, Ho, x = 0 3) com poundshavebeeninvestigated by X ray diffraction and magnetization measurement. Thesec ompounds have hexagonal Th2 Ni17 typestructure. The unit cell volumes decrease with the increaseof Crcontentx. The Curietemperature Tcincreasesobviously withincreasing Crcon tent x. The maximum increaseis about100 Kat x = 1 0 . Thesaturation magnetization of thesecompoundsshowsan approximatelylinear decrease with theincreaseof x.

Key words: unit cellvolume Curietemperaturesaturation magnetization