INVESTIGATION OF WALL THICKNESS EFFECT ON THE SPECIFIC ENERGY ABSORPTION OF ADDITIVELY MANUFACTURED GYROID LATTICES

In this study, the effect of wall thickness on the compressive behavior and energy absorption capacity of 3Dprinted polylactic acid (PLA) specimens was systematically investigated. A total of four type cubic sampleswith dimensions of 20 × 20 × 20 mm were fabricated using a Bambu Lab A1 printer at a nozzle temperature of220 °C and a build plate temperature of 65 °C. Four different wall thicknesses (1, 2, 4, and 6 mm) wereconsidered, while the infill density was kept constant at 30%. Compression tests were conducted on a Raegenuniversal testing machine under a displacement-controlled loading rate of 1 mm/min, and the resulting force–displacement data were recorded for subsequent analysis. From these curves, absorbed energy and specificabsorbed energy values were calculated to evaluate the crashworthiness performance of the samples.Furthermore, post-failure images of the specimens were examined to identify the dominant failure mechanismsas a function of wall thickness. The results revealed a clear dependence of compressive strength and energyabsorption on wall thickness, with thinner-walled structures exhibiting more progressive deformation and largerdisplacements, whereas thicker-walled specimens showed higher peak forces but lower energy absorptionefficiency per unit mass. The failure modes also shifted from ductile-like crushing and cell collapse in thin wallsto brittle fracture and localized shear in thick walls. Overall, the findings demonstrate that tailoring wallthickness provides an effective design parameter to optimize the balance between load-bearing capacity andenergy absorption efficiency in PLA components manufactured by fused deposition modeling.