Abstract:
Wire-arc additive manufacturing (WAAM) is a directed-energy deposition technology that uses arc
welding procedures to produce computer-aided designed parts, such as three-dimensional printed
metal components. A challenge of additive manufacturing is the anisotropy. Interstitial elements play
a significant role in the mechanical properties of Ti6Al4V of different grades. In this research, the
mechanical properties of Grade 5 and Grade 23 Ti6Al4V were compared for this application. Samples
were extracted from WAAM-produced Ti6Al4V walls in different directions (horizontal and vertical) and
at different positions (top and bottom). The samples were subjected to optical microscopy and tensile
and hardness tests. Grade 5 Ti6Al4V samples were found to have greater strength, greater hardness,
and lower ductility, owing to the higher content of interstitial elements compared with Grade 23. The
bottom samples had higher strength than the top samples, which is attributed to thermal cycling during
manufacturing, resulting in different microstructures.
