Influence of operating parameters on the mechanical and geometric properties of 316L Stainless Steel structures fabricated by WAAM-CMT

Wire Arc Additive Manufacturing (WAAM) is an advanced fabrication technique that uses wire as feedstock and an electric arc as a heat source to build metal components layer by layer. Known for its high deposition rates and cost-effectiveness, WAAM is particularly suited for large-scale, complex structures. In this study, a design of experiments was used to investigate the influence of operating parameters on the mechanical and geometric properties of 316L stainless steel walls. Multi-layer and multi-pass (each layer with two U-shaped beads) walls were deposited using the WAAM process with Cold Metal Transfer (CMT) technology. The "Zigzag" strategy, where the endpoint of one layer is the start of the next, was employed to ensure uniform wall height. The substrate used was a 304L stainless steel plate, mounted on an aluminum support to reduce distortions from residual stresses and improve heat dissipation. Machining and micrographic analysis were performed after the additive manufacturing process to evaluate the surface quality and internal structure. The results demonstrated that the operating parameters significantly influenced the geometric precision of the walls. Thermal interactions between layers and within beads played a key role in determining final wall characteristics, and careful parameter control is essential to optimize both geometry and mechanical performance.