Processing of gadolinium–iron garnet under non-equilibrium conditions.

We have investigated the mechanosynthesis of gadolinium iron garnet (GdIG) by high-energy ball-milling of 3.(Gd₂O₃) + 10.(<italic>α</italic>-Fe) followed by thermal annealing conducted at moderate temperatures (1100 °C). The samples were characterized by X-ray diffraction and Mossbauer spectroscopy in order to determine the influence of the milling time on the final products. For as-milled samples the results revealed the enlargement of the magnetic component belonging to iron and a discrete paramagnetic component. The formation of a garnet phase was observed in all as-annealed samples treated at 1100 °C for 6 h in quantities proportional to the time of grinding the precursors. Evidently, high-energy ball milling of Gd₂O₃ + <italic>α</italic>-Fe powders is an important step in GdIG synthesis by a ceramic method. Single-phase garnet is observed for the samples milled for 12 and 24 h treated at 1100 °C for 6 h. [ABSTRACT FROM AUTHOR]