On Mesoscale Numerical Modelling of Fused Deposition Modelling of Wood Fibre-Reinforced PLA Biocomposite

The increasing popularity and rapid advancements in Fused Deposition Modelling (FDM) have greatly expanded the spectrum of available materials for this technology. Among these materials, fully organic biodegradable PLA-based composites, enriched with a variety of organic additives, have emerged as a fully green and cost-effective alternative to conventional commercial FDM filaments. However, it is crucial to acknowledge that the incorporation of organic additives significantly influences the mechanics of the printing process and introduces complexities into the intricate process-structure–property interrelationship. This increased complexity may give rise to various challenges, such as the formation of defects, nozzle clogging, and even the failure of components during fabrication. Therefore, there is an urgent imperative to advance our understanding of the FDM process when utilizing biocomposite materials. Equally important is the development of computational tools capable of predicting and mitigating defects in biocomposite components produced through FDM. In response to this demand, the present study introduces a mesoscale numerical model specifically tailored for biocomposite materials. This innovative numerical model successfully captures the formation of defects in PLA/wood composites manufactured using varying layer heights. Importantly, the numerical results align closely with experimental findings. Moreover, the model identifies the formation of wooden sublayers at the peripheries of deposited layers as a potential factor contributing to reduced layer bonding and the overall occurrence of defects.