Multi‐objective optimization of laser heat flux distribution considering interlaminar shear strength and warping in laser‐assisted automated fiber placement

Abstract The laser‐assisted automated fiber placement (LAFP) in‐situ consolidation process shows great potential in the industrial sector. However, its practical application in engineering is hindered by the low interlaminar shear strength (ILSS) and warping of components. This study optimized the distribution of laser heat flux using the non‐dominated sorting genetic algorithm‐II to enhance ILSS and reduce warping of LAFP in‐situ consolidation carbon fiber reinforced polyetheretherketone (CF/PEEK) laminates. A laser irradiation model was developed to calculate the laser heat flux distribution during the LAFP process, and a thermal‐mechanical coupling model was created to conduct finite element analysis of the LAFP process. Afterwards, the laser heat flux distribution was optimized using NSGA‐II based on the computed temperature histories. The selected parameters from optimization findings were used to conduct placement experiments, and then the ILSS and warping of the CF/PEEK laminates were measured. After optimization, the maximum ILSS achieved was 81.46 MPa at a placement speed of 100 mm/s and a consolidation force of 300 N, which represented 90.5% of the hot compression molding (90 MPa) with the same material. In addition, it is feasible to significantly reduce the central axis warping (37.6% reduction) at the cost of reducing ILSS (6.6% reduction). Highlights Propose an inversion design method for laser spatial pose and laser power. Propose a method for coupling optimization of ILSS and warping. Propose a thermal‐mechanical model for LAFP considering laser heat flux load.