This research employs the Taguchi method and analysis of variance (ANOVA) to investigate, analyze, and optimize the impact strength of tough polylactic acid (PLA) material produced through fused deposition modeling (FDM). This study explores the effect of key printing parameters—specifically, infill density, raster angle, layer height, and print speed—on Charpy impact strength. Utilizing a Taguchi L16 orthogonal array experimental design, the parameters are varied within defined ranges. The results, analyzed through signal-to-noise (S/N) ratios and ANOVA, reveal that infill density has the most substantial impact on Charpy impact strength, followed by print speed, layer height, and raster angle. ANOVA identifies infill density and print speed as the most influential factors, contributing 38.93% and 36.51%, respectively. A regression model was formulated and this model predicted the impact strength with high accuracy (R² = 98.16%). The optimized parameter set obtained through the Taguchi method, namely, a 100% infill density, 45/−45° raster angle, 0.25 mm layer height, and 75 mm/s print speed, enhances the impact strength by 1.39% compared to the experimental design, resulting in an impact strength of 38.54 kJ/m². Validation experiments confirmed the effectiveness of the optimized parameters.

This study investigates the additive manufacturing (AM) process of 30% ceramic‐reinforced composite PLA material using the fused deposition modeling (FDM) technique. The effects of various printing parameters on tensile strength, build time, and material consumption are comprehensively analyzed through a combination of the Taguchi method, analysis of variance (ANOVA), and gray relational analysis (GRA). Experimental design parameters include nozzle diameter, infill density, infill pattern, wall line count, print speed, and layer height. Statistical analyses reveal significant contributions of these parameters to mechanical properties and production efficiency. Single and multi‐objective optimizations of the responses were performed. The single optimization resulted in a significant increase in tensile strength from 39.9 to 48.10 MPa. Production time was reduced from 16 to 9 min; material consumption decreased from 4.95 to 2.43 g for tensile test specimens. The use of GRA in multi‐objective optimization has led to a significant improvement of 8.31% in the gray relational grade (GRG) when compared to the initial parameter settings. These findings provide valuable insights for optimizing FDM processes in the fabrication of composite PLA materials. This contributes towards the advancement of additive manufacturing technology and its applications across various industries. and its applications across various industries.Highlights: Tensile strength increased while reducing build time and material consumption. Optimal printing parameters were identified for a composite PLA material. Layer height and nozzle diameter were effective parameters.

Additive manufacturing (AM), particularly fused filament fabrication (FFF), has gained significant attention for its design flexibility and cost-effectiveness. This study focuses on optimizing FFF parameters that employ response surface methodology (RSM) to enhance the flexural performance of polyethylene terephthalate glycol (PETG) parts. Three essential parameters—layer height, print speed, and nozzle temperature—were varied, and their effects on flexural strength, flexural modulus, flexural toughness for ultimate strength, flexural toughness at 5% strain, and strain at ultimate strength were evaluated. Based on a Box–Behnken design, the experiments revealed significant effects of these parameters on the mechanical responses. The analysis of variance (ANOVA) indicates that layer height predominantly affects flexural modulus and toughness, while nozzle temperature significantly impacts flexural strength. The RSM models exhibited high accuracy, with R² values exceeding 99%. Optimal parameter combinations yield remarkable improvements: flexural strength reached 39.55 MPa, flexural modulus peaked at 1344.60 MPa, flexural toughness for ultimate strength reached 218.22 J/mm³, flexural toughness at 5% strain reached 381.47 J/mm³, and strain at ultimate strength reached 3.50%. Validation experiments confirm the effectiveness of the optimization, with errors below 3.17%.

AA6082-T6 alloy was joined by friction stir spot welding using five different pin profiles, namely cylindrical, conical, triangular, hexagonal, and cylindrical with two grooves, at different dwell time. The joints welded by cylindrical pins had larger effective weld width. However, grooves on the cylindrical pin decreased the effective weld width. In the weld made with the hexagonal pin, the hook was bent downward from the interface of the sheets and had the smallest effective weld width. When the conical pin was used, the effective weld width increased with increasing dwell time. In the case of using tools with cylindrical and conical pins, HAZ hardness was relatively lower. With increasing dwell time, HAZ hardness of the joints made with the conical pin decreased. Effective weld width determined the weld strength under the tensile shear loading condition: larger effective weld width resulted in higher weld strength. Weld strength of the joints made with cylindrical pins was higher. The joints fabricated with hexagonal pins had the lowest weld strength. In general, higher dwell time led to higher weld strength. The welds with the higher strength experienced both brittle and ductile fractures, while the joints with the lower strength exhibited completely brittle fracture.