Comparison of Structural and Mechanical Properties of Heat-treated Ti-6al-4v Alloy Obtained by Additive Manufacturing and Metallurgical Routes

This study is devoted to the structural and mechanical properties of Ti-6Al-4V alloy in the as-received state obtained by various 3D printing approaches – selective laser melting (SLM) and wire arc additive manufacturing (WAAM), as well as to evolution of the properties under different heat treatment parameters. The obtained results were compared with a conventionally produced industrial counterpart – an electrometallurgical ingot, hot-rolled into a rod. The results suggest significant differences in microstructure (e.g., grain size, phases distribution and morphology), phase composition, and mechanical properties between additively manufactured materials and hot-rolled counterparts. Moreover, the applied heat treatment procedures directly influence the structural homogeneity, the degree of crystal lattice distortion, formation of the martensitic phase, and the dispersion of secondary phases, determining the microhardness of the investigated t materials.Thus, it is shown that mechanical properties of the Ti-6Al-4V alloy could be effectively controlled by selection of the appropriate manufacturing technology and heat treatment conditions.