Energy-driven decision support tool for friction stir additive manufacturing operations

Friction Stir Additive Manufacturing (FSAM) allows the production of components by stacking and joining sheets via friction stir welding. FSAM's energy efficiency depends on the number of passes needed to achieve a specified build width. This study introduces a single-pass, pinless FSAM method for producing AA5754-H22 components. Mechanical tests showed performance comparable to traditional FSAM, with bonding efficiency between 91 % and 94 % of the base material. Energy evaluations for two industrial scenarios revealed that a pinless approach should be preferred over FSAM when a single-thickness approach is used with sheets of thicknesses lower than 4 mm. When a sheet thickness of 5 mm is considered, lower electrical energy consumption is obtained for build heights of 11 mm and higher. In a multi-thickness approach, the proposed approach is energetically effective with build height lower than 16 mm. Life Cycle Assessment (LCA) examined the environmental impact, including material considerations. The single-thickness pinless method (4 mm, 5 mm, and 1 mm cases) was analyzed using Cumulative Energy Demand (CED). For heights up to 18 mm, the pinless approach minimized or matched CED. However, for heights that are multiples of 5 mm, traditional FSAM showed advantages. At 17 mm, energy savings of 16 % and 9 % were achieved for 4 mm and 5 mm cases, respectively. In terms of Global Warming Potential, the pinless approach matched the single-thickness 4 mm case with an impact of 7.704 kgCO2,eq. Overall, the pinless method is preferable for most target heights.