| Abstract Scope |
Wire arc additive manufacturing (WAAM), a directed energy deposition (DED) process, generates surface oxides during layer deposition due to high-temperature exposure. These oxides impair weld pool wetting, degrading surface quality and dimensional accuracy, while entrapped oxides form nonmetallic inclusions that reduce ductility, fatigue resistance, and overall mechanical performance. The issue intensifies with increasing part size and interpass temperatures, as prolonged heat exposure accelerates oxidation and limits natural oxide dissociation. This study quantifies the impact of surface oxides on mechanical properties. Several in-process mitigation strategies are evaluated and compared: oxide-reducing fluxes, mechanical interlayer cleaning, laser-based oxide ablation, and controlled additions of trace hydrogen to the shielding gas. Findings provide practical guidance for producing higher-quality WAAM components and opportunities for additional research. |