Andri Nasution, Muhammad Luthfi Hakim, Herianto Herianto, Achmad Pratama Rifai
Advances in additive manufacturing, particularly multi-nozzle fused deposition modeling (FDM), enable the fabrication of multi-material composites with tailored mechanical properties. In this study, sandwich structures composed of PLA, ABS, and HIPS were systematically evaluated in six layer-ordering configurations under a Taguchi L27 experimental design. Seven process parameters layer thickness, raster angle, build orientation, raster width, print speed, infill density, and material sequence were varied, and flexural performance was quantified using ASTM D6272 four-point bending tests, supported by interfacial microscopy. The results show that the ABS–PLA–ABS configuration achieved the highest flexural strength, with a maximum of 64.96 MPa, whereas PLA-faced laminates such as PAP displayed brittle fracture and lower strain-to-failure. Configurations with ductile outer layers (ABS, HIPS) exhibited greater energy absorption and reduced variability, consistent with microscopy evidence of fewer voids and improved interfacial bonding. By contrast, PLA-faced laminates revealed larger voids and uneven interfaces that acted as crack initiation sites. This work demonstrates that both process optimization and material placement govern ductile-to-brittle transitions in multi-material FDM structures. The findings provide practical guidelines for optimizing printing parameters and material placement to enhance flexural performance. © The Author(s), under exclusive licence to The Brazilian Society of Mechanical Sciences and Engineering 2025.
Department of Mechanical and Industrial Engineering, Faculty of Engineering, Universitas Gadjah Mada, Jalan Grafika No. 2, Yogyakarta, 55281, Indonesia; Department of Industrial Engineering, Universitas Sumatera Utara, Padang Bulan Street, North Sumatera, Medan, 20155, Indonesia; Department of Electrical Engineering Education, Faculty of Engineering, Universitas Negeri Yogyakarta, Jl. Colombo No. 1, Yogyakarta, 55281, Indonesia
