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 + + ⇄ 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.