Multi-objective optimization of FDM process parameters for GF/rPP composites using multi-criteria decision-making

This study performs multi-objective optimization of fused deposition modeling (FDM) process parameters for glass fiber-reinforced recycled polypropylene (GF/rPP) composites to improve tensile strength while reducing build time and material consumption. A Taguchi L27 array based on a four-factor, three-level design was used to investigate the effects of printing temperature, layer thickness, infill density, and raster angle on printing performance. The main effects analysis and analysis of variance (ANOVA) results indicate that infill density has the greatest influence on tensile strength and material consumption, with contributions of 44.79% and 90.52%, while layer thickness is the primary factor affecting build time, contributing 46.92%. Subsequently, a multi-criteria decision-making method was proposed to rank the printing alternatives, and the optimal parameter combination was determined to be printing temperature 240°C, layer thickness 0.2 mm, infill density 60%, and raster angle 0°. Compared with the average performance of all experimental alternatives, this optimal alternative reduces the build time by 15.36% and material consumption by 10.37%, at the cost of only a slight reduction of 3.08% in tensile strength. Finally, sensitivity analysis, comparisons with other decision-making methods, and scanning electron microscopy observations were used to further validate the stability and effectiveness of the proposed method.