In situ Al3Ti/Al composites fabricated by high shear technology: microstructure and mechanical properties

In situ Al3Ti/Al composites were produced by the reaction between Ti powder and Al melt with high shear technology. As Ti powder is starting material, it is important to investigate its size effect on the microstructure and mechanical properties of Al3Ti/Al composites. The results indicate that the necessary reaction time increases with increasing Ti particle diameter, which results in the Al3Ti phase coarsening. Particle sedimentation occurs at a short mixing time applying large Ti powder. Due to the presence of stiff Al3Ti particles, Young's modulus increases with particle volume fraction and fit well with the predicted values from the Halpin?Tsai equation. Moreover, together with grain refinement, these Al3Ti particles with a homogeneous distribution also lead to an increase in tensile strength.