Effect of Ce, Co, B on formation of LaCo13-structure phase in La(Fe, Si)13 alloys

The effect of Ce, Co, and B on the formation of 1:13 phase in La(Fe, Si)13 alloys was investigated by XRD, SEM and EDS. The results show that Co can improve the formation of 1:13 phase in as-cast LaFe11.6−xCoxSi1.4 alloys, but in as-cast and annealed LaFe11.6Si1.4−xCox alloys, it will hamper the formation of 1:13 phase and help the formation of α-Fe(Co, Si) solid solution. Ce2Fe17 phases will form when x reaches a certain value in as-cast and annealed La1−xCexFe11.5Si1.5 alloys. B can improve the formation of 1:13 phase accompanied with Fe2B phase in as-cast LaFe11.6−xBxSi1.4 alloys. B improves the formation of α-Fe solid solution in LaFe11.6Si1.4−xBx alloys, and there is almost only α-Fe in as-cast and annealed LaFe11.6Si0.9B0.5 alloy. In all, the introduction of Co, B, and Ce cannot eliminate the α-Fe phases in corresponding alloys prepared by the high-temperature and short-time annealing process.