Defects and residual stresses finite element prediction of FDM 3D printed wood/PLA biocomposite

The exploited enthusiasm within the research community for harnessing PLA-based biocomposites in fused deposition modeling (FDM) is spurred by the surging demand for environmentally sustainable and economically viable materials across diverse applications. While substantial strides have been taken in unravelling the intricacies of the process-structure-property relationship, the intricate interdependencies within this context remain only partially elucidated. This current gap in knowledge presents formidable obstacles to achieving the pinnacle of quality and dimensional precision in FDM-fabricated specimens crafted from biocomposites. Despite the existence of numerous numerical models for simulating the FDM process, an unmistakable need exists for models that are custom-tailored to accommodate the distinct characteristics inherent to biocomposites. As a reaction to those pressing needs, this study presents a 3D coupled thermomechanical numerical model designed to predict dimensions, defect formation, residual stresses, and temperature in PLA/wood cubes produced by FDM, considering various process parameters and composite-like nature of wood-filled PLA filaments. The accuracy of the proposed numerical model was validated by comparing its results with experimental measurements of biocomposite cubes manufactured under the same process parameters. Encouragingly, the simulated dimensions showed a maximum relative error of 9.52% when compared to the experimental data, indicating a good agreement. The numerical model also successfully captured the defect formation in the manufactured cubes, demonstrating consistent correspondence with defects observed in the experimental specimens. Therefore, the presented model aims to substantially contribute to the progress in the field of additive manufacturing of PLA-based biocomposites.