Tensile performance of multi-material sandwich structures fabricated by multi-nozzle fused deposition modeling using PLA, ABS, and HIPS

This study investigates the tensile and interfacial bonding behavior of six multi-material sandwich structures APA, PAP, HPH, PHP, AHA, and HAH fabricated using a multi-nozzle fused deposition modeling (FDM) printer with PLA, ABS, and HIPS. A systematic variation of seven process parameters layer thickness, raster angle, build orientation, raster width, print speed, infill density, and core composition was conducted using a Taguchi L27 orthogonal array. Among all configurations, APA exhibited the highest tensile strength of 48.03 MPa and a modulus of 796.17 MPa, outperforming PAP (42.07 MPa) and HPH (38.07 MPa) by approximately 10�15 , attributed to superior interlayer fusion and balanced material synergy. Raster angles aligned at 45° and 90°, particularly when combined with 0° build orientation and moderate raster width, further improved the mechanical performance, especially in PLA- and ABS-based structures. Microscopic and fractographic observations reinforced these findings, revealing that APA exhibited denser layer fusion and fewer interfacial voids, contributing to its superior structural integrity. PETG was excluded due to poor adhesion with PLA and ABS under comparable conditions. These findings highlight how parameter optimization and strategic material pairing in sandwich configurations enhance performance, indicating their applicability in lightweight structural applications such as UAV frames, protective enclosures, or biomedical supports. © 2025