ANNEALING AND MAGNETIC-FIELD EFFECTS ON THE RESISTIVITY OF FE-RICH FE-ZR GLASSES

Electrical resistivity at zero and applied magnetic fields has been me asured in as-quenched and annealed Fe91Zr9 and Fe90Zr10 amorphous allo ys between 4 and 320 K. Fe91Zr9 remained amorphous after annealing at 400 K (1 h) while in Fe90Zr10, traces of crystallites were observed. S imilar annealings at 600 K were sufficient to crystallize both alloys, with alpha-Fe as the main product. A.c. susceptibility shows small ch anges in the Curie and spin-glass temperatures upon annealing. The res istivity displays a minimum at high temperatures (congruent to 250 K), slightly influenced by a magnetic field and thermal treatment. The re sistivity is a competition of contributions in which the structure pla ys the most important role. The presence of magnetic inhomogeneities c ould also favor an enhanced electronic localization. (C) 1997 Elsevier Science Ltd.