Simulation of residual stress and distortion evolution in dual-robot collaborative wire-arc additive manufactured Al-Cu alloys

The aim of this study is to evaluate the residual stress and deformation distribution of large thin-walled Al-Cu alloy components produced by a dual-robot collaborative system in wire-arc additive manufacturing. Finite element models of single-robot and dual-robot systems were developed and experimentally validated using infrared thermography and structured light sensors. The dual-robot achieved significantly lower maximum temperature gradients in both deposition (0.47 × 10⁵ ℃/m vs. 0.68 × 10⁵ ℃/m) and height directions (0.94 × 10⁵ ℃/m vs. 1.03 × 10⁵ ℃/m) compared to the single robot, indicating more uniform temperature distribution. The stress evolution process and distribution between the single robot and dual-robot systems differs, but both exhibit approximately symmetric distributions. Moreover, the dual-robot reduced vertical displacement in the substrate by approximately 29% (15.2 vs. 21.4 mm), attributable to more uniform stress distribution and reduced temperature gradients. The additive manufacturing of a commercial aircraft load-bearing frame validated the application potential of this technology in the industry.