Formation of Small Blocky Al3Ti Particles via Direct Reaction Between Solid Ti Powders and Liquid Al

The evolution of titanium powders in the pure aluminum melt at a lower temperature was studied in our research. The process involved some titanium powders being added into the pure aluminum melt at 1003 K (730 A degrees C), and then the melt was cast into an ingot after 5 minutes. A reaction layer composed of some loose Al3Ti particles was formed on the solid Ti surface due to the reactive diffusion between titanium and aluminum. In-situ blocky Al3Ti particles smaller than 5 mu m were produced in the aluminum matrix. A reaction-peeling model was suggested to illustrate the formation mechanism of Al3Ti particles, and a simple approach for fabricating in-situ Al3Ti/Al-alloy composites was proposed as well.