The growing demand for complex structures, energy absorption, and mechanically strong materials has led to the exploration of innovative composites. This study focuses on the manufacture, characterization, and evaluation of PLA+ reinforced with woven glass fiber. Using Fused Filament Fabrication (FFF) 3D Printer technology, the effects of adding woven glass fiber were examined through a tensile test with Digital Image Correlation (DIC)-induced, flexural, Charpy impact resistance, Shore D hardness, Differential Scanning Calorimetry (DSC) thermal tester, and SEM morphological tests. Results showed that adding four layers of glass fiber significantly improved mechanical properties: tensile strength increased by 85% to 95.44 MPa, flexural strength by 13% to 91.51 MPa, and impact resistance by 450% to 15.12 kJ/m². However, a reduction in hardness and thermal resistance was noted due to chemical interactions. These findings suggest potential applications of PLA+ composites in high-strength products for vehicle bumpers in the automotive industry and shin pads in the sports industry.

To improve energy dissipation during impact on a 3D printed material, this study introduced a preliminary study on sandwich structure of polylactic acid/thermoplastic polyurethane under impact loading. The sandwich structure used an origami structure as the main core to improve energy absorption during impact. The energy absorption characteristics were analysed using finite element methods (FEMs) and further validated using experimental methods. In this study, we used a Miura as the core for the sandwich structure. The fabrication method was fused deposition modelling. The experiment impact test result indicated that the sandwich structure using the Origami structure absorbed approximately 25% of the impactor energy. Comparing this experimental result to the FEM revealed an error rate of less than 5%. Based on our numerical and experimental methods, we found that the wall thickness of the origami core structure significantly impacts the absorbed energy. Increasing the core wall thickness twice from the original design increases energy absorption to approximately 89%. This demonstrates the validity of the FEM to predict the experimental outcome. The influences of the core thickness on the response of the overall structure led to optimal design, maximizing the energy dissipation in the 3D-printed sandwich structure.