How do Printing Parameters Influence the Tensile Performance of 3D-Printed Lightweight Structures: A Comprehensive Analysis and Optimization Approach?

3D printing enables the creation of lightweight cellular structures, balancing high strength and stiffness, enabling complex shapes that are challenging to achieve with conventional manufacturing methods. Subsequently, this study seeks to optimize the printing parameters of advanced polylactic acid (PLA+) structures to maximize their mechanical performance under tensile loading. For this reason, four key design parameters, the layer height, the infill pattern structure, the infill density, and the nozzle temperature, each at three levels, were selected. The design of experiments framework has employed the Taguchi approach to determine the ideal parameters for attaining the optimum tensile performance. A number of experiments were carried out using the L9 orthogonal array. Through the largest ultimate tensile strength (\(\sigma_{{{\text{ult}}}}\)), failure strain (\(\varepsilon_{{\text{f}}}\)), tensile modulus (\(E\)), and toughness modulus (\(U_{{\text{T}}}\)), the optimal parameters were established. The analysis demonstrated that the studied parameters significantly impact the tensile performance of PLA+. According to the accomplished analysis, infill density has the largest influence on the value of \(\sigma_{{{\text{ult}}}}\), \(E\), and \(U_{{\text{T}}} \) with an influence percent of 76.072, 85.062, and 55.116%, respectively. However, nozzle temperature has the most significant influence on \(\varepsilon_{{\text{f}}}\) with 48.668% influence percent. Moreover, the error percentages for \(\sigma_{{{\text{ult}}}}\), \(\varepsilon_{{\text{f}}}\), \(E\), and \(U_{{\text{T}}}\) based on the confirmation tests are 2.945, 13.051, 6.480, and 10.520%, respectively.