The effect of heat treatment on amorphous Fe74Zr19Ta7 and Fe90Y10 alloys

Publisher Website
Google Scholar
Abstract
Magnetic measurements are reported for two iron‐based amorphous alloys: Fe90Y10 and Fe74Zr19Ta7. Each is prepared by sputter deposition. X‐tay diffraction is used to established the amorphous structure and X‐ray fluorescence analysis to confirm the composition. Fe74Zr19Ta7 has a Curie temperature of 195 K and a crystallization temperature of 733 K (460 °C). Annealing studies on Fe74Zr19Ta7 indicate that this alloy does not show the dramatic increases in Curie temperature that are commonly observed in amorphous alloys that contain metalloid elements. Rather, this alloy exhibits small irreversible decreases in the Curie temperature following heat treatments up to 733 K (460 °C), the crystallization temperature. The amorphous Fe90Y10 alloy shows only short range order and has a large anisotropy field that prevents the saturation of the magnetic moment in a 10 kOe field at 78 K. The anisotropy decreases upon crystallization to a bcc iron structure, but ferromagnetism is observed only after annealing the alloy at elevated temperatures.