Multi‐criteria decision‐making for optimizing crashworthiness of <scp>3D</scp>‐printed <scp>PETG</scp>‐<scp>CF</scp> lightweight structures: Influence of printing parameters

Abstract This work investigates the effect of printing parameters on the crashworthiness performance of square tubes made with polyethylene terephthalate glycol reinforced with carbon fiber (PETG‐CF). This was accomplished by analyzing three printing parameters, infill pattern structure, infill density, and layer height, each of which changed across four levels. The specimens' structural performance was then assessed using quasi‐static axial compression testing. In addition to carefully documenting failure histories, data on crash load, absorbed energy, and displacement responses were methodically recorded during the testing. Several critical performance measures, including the initial peak crash load (), the total energy absorbed (U), the mean crash load (), the specific absorbed energy (SEA), and the crash force efficiency (CFE), were used to evaluate crashworthiness. A complex proportional assessment (COPRAS) method, was employed to determine the optimal configuration. The results indicate that the honeycomb structure achieves the highest values for , U, , and SEA, with measurements of 5.57 kN, 250.54 J, 4.64 kN, and 15.27 J/g, respectively. Meanwhile, the Schwarz P attains the maximum CFE, with a value of 1.585. The COPRAS results further indicated that the HC‐30‐0.20 configuration exhibited the best crashworthiness performance. Highlights The designed configurations were created using FDM. The tubes were exposed to axial compression loads. The crashing load and energy absorption curves against displacement were computed. Besides, the crashing histories were detected. Furthermore, the COPRAS method is used to catch the optimal structure.