The composition dependence of the structural and magnetic properties in Fe92-xBxZr7Cu1 nanocrystals

Melt-quenched amorphous Fe92-xBxZr7Cu1(2 less than or equal to x less than or equal to 23) ribbons were heat treated to the end of the first crystalli zation stage. The size of the BCC grains decreases from 20 to 6 nm with inc reasing B content, while the average thickness of the residual amorphous ph ase stays approximately constant at about 4 nm. The nanocrystalline BCC pha se contains 2-4 at% of dissolved B and Zr, which is also reflected in its m odified Curie temperature. The average composition of the residual amorphou s regions in the nanocrystalline composite was established as Fe-2(B1-yZry) , which makes possible a direct comparison of macro- and nanophases of clos e composition. (C) 2000 Elsevier Science B.V, All rights reserved.