The 520 °C Isothermal Section of the Phase Diagram of the Ternary Dy-Fe-Si System.

The 520°C isothermal section of the Dy–Fe–Si system was investigated by X-ray powder diffraction, differential thermal microanalysis and electron-probe microanalysis techniques. At 520°C, it consists of 21 single-phase regions, 46 two-phase regions and 26 three-phase regions. The existence of eleven binary compounds and seven ternary compounds was conformed. Among seven ternary compounds. DyFe3Si6 and DyFe11Si are new phases, which belong to the hexagonal system with a=0.3931 nm, c=1.5431 nm and tetragonal system with a=0.8519 nm, c=0.4780 nm, respectively.