MAGNETIC-PROPERTIES OF DY2FE17-XCRX AND ER2FE17-XCRX (X=0-3) COMPOUNDS

The crystal structure and magnetic properties of R2Fe17-x Cr-x(R = Dy, Er, 0 less than or equal to x less than or equal to 3) compounds have been investigated by means of X-ray diffraction and magnetization mea surements. These compounds have hexagonal Th2Ni17-type structure. The unit-cell volumes decrease with the increase of Cr concentration x. Th e Curie temperature T-C of the Er2Fe17-xCrx compounds increases from 3 20K for x = 0 to 403 K for x = 1.0 and then decreases with further inc rease of x. The Curie temperature Te of Dy2Fe17-xCrx compounds increas es from 364 K for x = 0 to 435 K for x = 1.0 and then decreases with f urther increase of x. The saturation magnetization of these compounds shows an approximately linear decrease with the increase of x. Spin re orientation transitions occurs in Er2Fe17-xCrz(x =2.0 and 3.0).