Mössbauer spectroscopy study of amorphous Fe87B11Au2 ribbon and its crystallization products

Substantial increases in Fe saturation magnetization have been obtained in amorphous Fe–B containing small concentrations of gold. This material is also stable above 300 K, and thus has considerable practical significance. We report the results of an investigation of amorphous Fe87B11Au2 ribbon and its crystallization products based on 57Fe Mossbauer spectroscopy. The amorphous ribbon exhibits a broad magnetic hyperfine splitting pattern typical of a metallic glass with an effective hyperfine field, Heff=257 kOe, and an isomer shift of 0.058 mm/s relative to metallic Fe at 300 K. The spectra of samples annealed for 25 min between TA=618 and 708 K arise from a metastable amorphous phase of Fe–Au–B and a crystalline α‐Fe phase. Heff of the metastable amorphous phase decreases with respect to increased annealing temperature. However, Heff of the α‐Fe phase increases from 331 kOe for samples annealed at 618 K to 334 kOe for those annealed at 708 K. This increase can be attributed to an increased content of Au...