Structure and thermal stability of amorphous Fe-Zr alloy

Amorphous Fe-Zr alloys were prepared near the eutectic composition with 10 at.% Zr by rapid cooling from the melt. The magnetic moment of Fe atoms and the Curie temperature of the amorphous alloys increase with increasing Zr concentration. This fact suggests that Zr atoms induce the magnetic moment of Fe atoms in the amorphous structure. On the other hand, the magnetic moment and the Curie temperature of vacuum deposited amorphous Fe-Zr films with more than 20 at.% Zr decreased with increasing Zr content. It is very interesting to examine if the models for the atomic arrangement in metal-metalloid amorphous alloys are applicable to metal-metal amorphous systems. In this study, the structure and thermal stability of amorphous Fe90Zr10 alloy were investigated by means of Moessbauer spectroscopy and X-ray diffractometry. The experimental procedure and the results are reported. The Moessbauer spectra of the amorphous Fe90Zr10 alloy indicated that the paramagnetic and ferromagnetic components coexisted in a wide temperature range below the Curie temperature of 240 K. The internal field distribution curve showed large and small peaks arising from the inhomogeneity of atomic arrangement. On annealing at 3000C a relaxation effect occurred, and the Curie temperature was reduced by 300K. (J.P.N.)