Isothermal Section of the Al-Mn-Dy System at 500 degrees C

Phase relationships in the Al-Mn-Dy ternary system at 500 A degrees C have been investigated by X-ray diffraction, scanning electron microscopy with energy dispersive spectroscopy, and electron probe microanalysis. From the experimental results it was concluded that the isothermal section consists of 16 single-phase regions, 26 two-phase regions and 12 three-phase regions. Two extensive solid solutions, (Al (x) Mn1-x )(12)Dy and (Al1-x Mn (x) )(2)Dy, were observed. The solid solution (Al (x) Mn1-x )(12)Dy forms by Al replacing Mn in Mn12Dy, while the continuous solid solution (Al1-x Mn (x) )(2)Dy forms by Mn and Al mutually substituting in Al2Dy and Mn2Dy, respectively. The maximum solid solubility of Al in Mn12Dy is 79.3 at.%.