Phase relation in the Pr-Ti-Al ternary system at 500 degrees C

The isothermal section of the Pr-Ti-Al ternary phase diagram at 500 degrees C wets investigated by powder X-ray diffraction, electron probe microanaly sis and differential thermal analysis. The 500 degrees C isothermal section of this ternary system consists or 14 single-phase regions, 26 two-phase r egions and 13 three-phase regions. Only one ternary compound Ti2Al20Pr was proved to exist in this isothermal section. A solid solution of the type Pr (Al Ti-1 - x(x))(2) was found in this work. At 500 degrees C, the maximum s olid solubility of Ti in Al2Pr is 17 at.% Ti and of Pr in Ti3Al and TiAl ar e less than 2 at. % Pr, respectively. (C) 2000 Published by Elsevier Scienc e S.A. All rights reserved.