A case study: Mechanical modeling optimization of cellular structure fabricated using wood flour-filled polylactic acid composites with fused deposition modeling

Wood plastic composites (WPCs) have emerged as environmentally benign filaments for fused deposition modeling (FDM) printing. Using WPCs filaments to print light weight and strong cellular structures could create new application potentials for WPCs and provide sustainable feedstock for cellular materials. In this research, the compression performance of FDM printed circle, square, and voronoi WPCs cellular structures were investigated using finite element simulations and compression experiments. Simulated results did not agree with experimental results due to the presence of cavities in the prints. Cavities were formed in the cellular structures with arcs and curvature. The results showed that the circle cellular structure demonstrated great fluctuations between the simulations and experimental results. The cavity porosity was also found to increase with the increase of the print line width. Further, to improve the accuracy of simulations, the cavity porosity exists in the cellular structures was considered while revising the models. After modification, square cellular models compressed the least, followed by the circle and voronoi ones, which was consistent with the experimental results. Minimizing the print line width could reduce cavity porosity. Nonetheless, thinner print line width and smaller wood fiber size in filaments will likely increase manufacturing cost and difficulty.