Rosadila Febritasari, Moch. Agus Choiron, Yudy Surya Irawan, Denny Widhiyanuriyawan
This study presents an optimized Double-Walled Hull Structural Filler Design (DWHSFD) based on a Double Arrowhead Auxetic (DAA) structure manufactured from AlSi10Mg using Selective Laser Melting (SLM). The effects of cell wall thickness (t), number of auxetic cells (n), and post–heat-treatment conditions (ht) were systematically examined. Taguchi analysis was employed to optimize heat-treatment parameters, including temperature, holding time, and aging time, resulting in stress relief at 300°C for 1 h, annealing at 450°C for 2 h, and T6 treatment consisting of solution treatment at 450°C for 1 h followed by water quenching and artificial aging at 150°C for 3 h. Response Surface Methodology revealed that the number of auxetic arrangements is the most influential factor governing specific energy absorption (SEA), followed by wall thickness and heat-treatment condition. The optimal DAA structure was identified as a structure with three arrowhead arrangements and a wall thickness of 1.8 mm. Quasi-static compression tests showed that stress-relieved specimens exhibited early crack initiation and the lowest crashworthiness performance. In contrast, T6-treated structures demonstrated the highest initial peak crushing force, while annealed specimens provided smoother deformation and more stable energy dissipation. Overall, the proposed DAA design demonstrates significant potential as an impact-mitigating filler for double-walled ship hulls and other marine protective applications. Therefore, the optimal heat-treatment condition should be selected according to application-specific requirements to achieve an appropriate balance between strength, ductility, and energy absorption performance. Copyright © 2026. Published by Elsevier B.V.
Department of Mechanical Engineering, Brawijaya University, Malang, 65145, Indonesia
