Combined effects of MgO reinforcement and thermal annealing on the mechanical and microstructural performance of FDM-fabricated ASA composites

This study investigates the combined effect of nanoparticle reinforcement and thermal annealing on the mechanical and microstructural properties of ASA-matrix, MgO-reinforced composites produced using the fused deposition modelling (FDM) method. The ASA matrix was reinforced with MgO at five different weight percentages (0–0.5–1–1.5–2), and the resulting specimens were thermal annealed. The mechanical properties were systematically investigated using impact strength, tensile strength, and surface hardness tests; the crystallographic properties were investigated using XRD analysis; and the properties of the fracture surface were investigated using SEM. The results indicated that both the reinforcement of MgO and thermal annealing improved the overall performance of the ASA matrix. After the annealing process at 70°C, the composite reinforced with 2% MgO achieved maximum tensile strength of 44.32 MPa, impact strength of 12.84 kJ/m ² , and Shore D surface hardness of 79.2. Compared to unreinforced (pure) ASA, tensile strength increased by approximately 13.4% and thermal conductivity improved by approximately 3.8%. SEM investigations revealed voids caused by FDM and MgO reinforcement, and XRD analyses revealed qualitative changes in the diffraction peak characteristics following thermal annealing. The results suggest that appropriate thermal annealing and reinforcement with MgO nanoparticles provide an effective approach to enhancing the performance of ASA composites produced via the FDM method for engineering applications.