An investigation of the effect of chemical composition and temperature on the resistance and hardness of thin amorphous Gd-Fe and Gd-Co systems

Abstract The effect of chemical composition on the resistance, the resistivity, the temperature stability of resistance and the hardness of thin amorphous Gd-Fe and Gd-Co films was investigated. The maximum resistivity (3.2 x 10 -6 Ω m) for Gd-Fe films was observed at 35 wt.% Fe and for Gd-Co films (3.5 x 10 -6 Ω m) at about 25 wt.% Co. Gd-Fe films with an iron content below 56 wt.% had a negative temperature coefficient of resistance (TCR). Positive TCR values were obtained at higher iron contents. For Gd-Co films positive TCR values were obtained at cobalt contents exceeding 43 wt.%. At compositions of 19.6, 41.0 and 43.0 wt.% Co the resistance was not temperature dependent in the range 20–120 °C. The hardness of the films increased with increase in the transition metal content, with maximum values of 7.0 x 10 9 N m -2 for Gd-Fe films and of about 8.7 x 10 9 N m -2 for Gd-Co films.