Intermetallic compounds in diffusion couples of Ti with an Al–Si eutectic alloy

Abstract

The phase equilibria in the Ti–Al–Si System have been studied in the temperature range 700–1000 °C using ternary diffusion couple experiment with pure titanium and high-purity Al–Si eutectic alloy. A number of binary and ternary intermetallic compounds have been observed. The intermetallics TiAl 2, Ti 9Al 23, TiAl and Ti 3Al form as solid layers. The intermetallics Ti 5Si 4 and Ti 5Si 3 are observed as two-phase layers associated with TiAl 3. Two ternary intermetallic compounds τ 1 and τ 2 with compositions close to Ti 3Al 2Si 5 and Ti 3AlSi 5 are observed. The microstructure of binary and ternary phases has been reported.