EQUILIBRIUM DIAGRAM OF THE Ti-Al-Sn SYSTEM

The equilibrium of ternary Ti-Al-Sn in the region of the partial system Ti-Ti/sub 3/Sn-TiAl was investigated. An analysis revealed a double system composed of Ti-Al and Ti-Sn solid solutions. The Ti-Al has an alpha -Ti base whicb forms between beta -phase Ti and-phase TiAl at 1240 deg C. The Ti-Sn has an alpha -Ti base which forms between beta -phase Ti and delta -phase Ti/sub 3/ Sn at 890 deg C. The phase diagram plotted for Ti-Al-Sn at 600 deg C showed phases of solid solutions of Al and Sn in alpha titanium ( alpha phase); solid solution with TiAl base ( gamma phase); continuous solid solutions of Ti/sub 3/ Al-Ti/sub 3/Sn compounds with alpha and delta phases; and TiSn solid solutions with a delta base. Microstructure examinations and x-raydiffraction analysis showed no tennary phase. (R.V.J.)