LAUSR

Abstract Refractory silicides, eutectic Si/MSi2 (M: Nb, Ta, Mo, or W) alloys, and high-purity silicon are materials that have been used in many high-tech industries. Today, they are prepared using different technologies, i.e., each of them is prepared using an independent technology. This study proposes a new method to simultaneously prepare three high-purity materials (refractory silicides, eutectic Si/MSi2 alloys, and silicon) using electromagnetic directional crystallization. The Si–M (Si–Nb, Si–Ta, Si–Mo, or Si–W) solvents are separated using electromagnetic directional crystallization, and then the MSi2 (NbSi2, TaSi2, MoSi2, or WSi2) and eutectic Si/MSi2 (Si/NbSi2, Si/TaSi2, Si/MoSi2, or Si/WSi2) alloys are precipitated in sequence because the crystallization temperature of MSi2 is higher than that of the eutectic Si/MSi2 alloys. Additionally, owing to the segregation behavior of impurities between the solid and liquid phases, impurities in the Si–M solvents can be eliminated efficiently to prepare high-purity MSi2 and eutectic Si/MSi2 alloys. In addition, as the eutectic Si/MSi2 alloys consist of Si and MSi2 phases, high-purity Si powders (>99.98%) can be obtained by separating the Si and MSi2 phases using acid leaching. The results indicate the feasibility of the new approach in preparing refractory silicides, eutectic Si/MSi2 alloys, and high-purity Si.