Study of the impact of the synergic line and the strategy of conception on Ti-6Al-4V wire arc additive manufacturing process (WAAM-CMT)

In additive manufacturing, technologies based on the fusion of a metallic wire using an electric arc represent an interesting alternative to current manufacturing processes, particularly for large metal parts, thanks to higher deposition rates and lower process costs than powder or wire-laser technologies. A versatile 3D printing device using a DED-W Arc (Direct Energy Deposition by wire-arc) station to melt a metallic filler wire is developed to build titanium parts by optimizing the process parameters and control the geometrical, metallurgical and the mechanical properties of produced parts. In this study, the impact of two different CMT synergic lines on the energetic and geometric behavior of Ti-6Al-4V single deposits is highlighted. These are related to first order parameters: wire feed speed (WFS) and travel speed (TS). The results show difference on energy, geometric of deposits and different deposition regime between these two law with identical process parameters. The second part of this study focuses on the transition from single deposits to walls and blocks. By first choosing the best set of process parameters to make the construction of thin walls (composed of stacked layers), and then the research the optimal horizontal step of deposition (overlapping) for thicker constructions, results obtained made it possible to validate transition from single deposits (1D) to thick walls (3D) without any weld pool collapse or lack of fusion