Intermetallic Compound Formation During Reaction of Molten Aluminum with Titanium

Abstract

A multistage process is described as the basis for metallographic studies of intermetallic formation during reaction of molten aluminum with titanium. A mechanism is proposed explaining the complex nature of the change in aluminide formation rate, including aluminide inclusion formation by breakdown. Stages are separated for reaction of titanium with molten aluminum: latent period; continuous intermetallic layer formation at a titanium-aluminum boundary; titanium dissolution in aluminum; band formation and growth within a melt with intermetallic fragments; increase in aluminide content in crystallizing melt. x-Ray structural and energy-dispersion analysis methods are used to demonstrate formation of just a single intermetallic TiAl₃, which confirms thermodynamic calculations performed by Kattner.