Phase Equilibria in the Aluminum Corner of the Al-Ti-Pt System.

A series of physicochemical analysis techniques are employed to study the phase equilibria in the aluminum corner of the Al-Ti-Pt system at subsolidus temperatures and in the alloy crystallization process. It has been established for the first time that a ternary τ1 phase (AuCu3 structural type) forms by peritectic reaction L + <Ti2Al5> + <TiAl> ⇄ τ1 at 1405°C. On the solidus surface in the studied composition range at 1405, 1310, 1275, 1060, 925, 820, and 660°C, there are seven isothermal planes that participate in invariant four-phase equilibria involving the liquid phase, three of them being peritectic and the others transitional. [ABSTRACT FROM AUTHOR]