Synthesis and Characterization of SmFe<SUB>12</SUB>-based compounds prepared by reaction-diffusion reaction

다국어 초록 (Multilingual Abstract)

The ThMn12-type structure has attracted attention as permanent magnetic material due to the high anisotropy field, saturation magnetization (Ms), and Curie temperature (TC). The Sm(Fe0.8Co0.2)11Ti (SFCT) materials have been intensively studied to synthesize high permanent magnets by controlling the doping element. In this study, we tried to investigate SFCT materials prepared by reaction-diffusion reaction. we prepared the Smx(Fe0.8Co0.2)11Ti (x= 1~4) precursor was prepared by a common co-precipitation method. The samarium nitrate hexahydrate, cobalt nitrate hexahydrate, titanium tetrachloride, and iron nitrate hexahydrate were dissolved in deionized water at 70 C to form a homogeneous solution. The 3M KOH solution was slowly dropwise in the solution. Then the pH of the solution was adjusted slowly to pH 12 by adding dropwise ammonium hydroxide solution. The precipitates
were collected by filtration. The precursors were heat-treated at 600℃ for 4h in H₂ gas. The hydrogen-reduced powders were mixed with calcium granules and pelletized. The pelletized samples were heated at 950 - 1050 ℃ for 1 h in Ar gas. Samples were characterized by using an x-ray diffractometer (XRD) with Cu-Kα radiation source, a vibrating sample magnetometer (VSM), and scanning electron microscopy (SEM). The samples were obtained ThMn12-type phase at 1050 ℃ for 1 h in Ar gas. The Ms and Hc values of Sm(Fe0.8Co0.2)11Ti samples were 95 emu/g and 1935 Oe. Detailed microstructures and magnetic properties will be presented for discussion.