Microstructure and Property of TiB-Reinforced Ti Alloy Composites by Laser Metal Deposition

Abstract

TiB-reinforced Ti alloy composites have been laser deposited with pre-alloyed Ti-6Al4V-1B powder. The microstructure of the as-deposited and heat treated composites have been characterized in detail using scanning electron microscope (SEM). A homogeneous dispersion of needle-like TiB precipitates is formed in the Ti-6Al-4V α/β matrix. TiB precipitates promote formation of small near equaxed α/β grain after β annealing process. The micro-hardness of the laser deposited composites increase 20-30% with 5 vol. % TiB precipitates compared to unreinforced Ti-6Al-4V deposits.