Low-temperature synthesis of Sm-Fe binary compounds by reduction-diffusion process using an eutectic salt solvent

In this study,the temperature of the low-temperature reduction-diffusion(LTRD)process was successfully decreased to below 600℃by introducing LiClKCl eutectic molten salt with a low eutectic point(352℃)as a solvent for Ca reductant.Therefore,the Sm-Fe binary compounds,which were synthesizable at previously-unexplored low temperatures by the LTRD process using LiCl-KCl eutectic molten salt,were investigated,including whether a new metastable or ThMn_(12)-type Sm-Fe binary phase was formed.The Sm-Fe phase transitions of the SmFe binary compounds at a low temperature were identified,and it was found that MgCu_(2)-type Sm-Fe,PuNi_(3)-type SmFe and TbCu_(7)-type Sm-Fe phases were synthesized and stable at 400,500 and 550℃respectively.Although no new metastable Sm-Fe and ThMn_(12)-type Sm-Fe compounds were discovered in this study,this work can demonstrate that it is possible to synthesize the Sm-Fe phase at very low temperatures by the LTRD process for the first time.