Effect of rare earth on morphology and dispersion of TiB2 phase in Al-Ti-B alloy refiner

To investigate the effect of rare earth on size and distribution of TiB2 phase in aluminum alloy refiner, Al-5Ti-1B-RE master alloy was fabricated, and its microstructure and phase constitutions were investigated by the combination of first principles calculations and experimental investigation. The calculated results reveal that Ce has the most effective modification ability due to the most positive adsorption energy and the largest charge transfer value compared with other rare earth elements. Results of experimental investigation indicate that the addition of rare earth in the Al-5Ti-1B alloys can greatly refine the particle size of TiB2, improve the distribution of particles and lead to better refinement effect than that of the Al-5Ti-1B alloys without rare earth. Moreover, Ce has the best optimization effect, which agrees well with the calculated results.