Parametric optimisation of 3D-printed PLA/wood dust composite for load-bearing application using grey relational analysis

This article proposes an investigation on sustainable polylactic acid/wood dust (PLA/WD) composite material for three-dimensional (3D)-printing applications. This eco-friendly material aids a remarkable reduction in thermoplastic waste, while minimising resource depletion, as a result it promotes circular economies, and mitigates environmental pollution. In order to extend the service life of manufactured components, it becomes necessary to investigate the key fused filament fabrication (FFF) processing parameters that affect the mechanical performance of PLA/WD composite parts. Taguchi-based L₂₇ orthogonal array composite design was implemented for experimentation, and mathematical models were developed by using grey relational analysis to predict the responses for the proposed material. Moreover, the FFF input parameters with three levels of values that were considered for the experimentation are the nozzle temperature (190°C–200°C), layer height (0.12–0.28 mm), print speed (30–50 mm/min), infill density (80–100%) and raster angle (0°–90°). The results revealed that the highest grey relational grade obtained was 0.8333 for the experiment run 19 with the sample having ultimate tensile strength and shore D hardness of 20.71 ± 1.24 MPa and 74 ± 2 SHD, respectively. Moreover, raster angle, layer height and infill density were found to be the influential parameters that affect the tensile and hardness properties of the sample. Furthermore, nozzle temperature of 200°C, layer height of 0.2 mm, print speed of 30 mm/min, infill density of 100% and raster angle of 90° were obtained as optimum FFF input parameters.