Reinforced biocomposites: Improvement of mechanical properties of 3D printed short carbon fiber reinforced PLA composites Via optimization

Thermoplastic polymers are widely used materials in the biomedical field due to their biocompatibility, ease of production and chemical stability; however, their mechanical properties are generally low. In this study, a short carbon fiber reinforced composite was produced to improve the mechanical properties of thermoplastic materials. Pre-processing and post-processing were applied to further improve the mechanical properties of the composite. Optimization of process parameters such as infill density and infill pattern and post-processing parameter such as annealing were performed. As a result of the experiments, the highest impact strength for PLA material is 18.98 kJ/m 2 and the lowest impact strength is 6.33 kJ/m 2 . In addition, the highest tensile strength was 44.68 MPa and the lowest tensile strength was 5.38 MPa. The reliability rates of tensile and impact strength analyses are 98.18% and 96.67%, respectively. SEM and XRD analysis indicated that the parameters affecting the product properties are not only critical for mechanical properties but also affect the internal structure. Mechanical properties and crystal percentage value increased by annealing the reinforced biocomposite at 90°C for 30 min. It has been determined that the build orientation (or printing direction) has a critical importance on the mechanical properties and the mechanical properties of the specimens obtained as a result of on-edge production are higher.