چكيده به لاتين
The technology of 3D printers is well recognized as one of the most important tools for producing three-dimensional objects with intricate and highly sophisticated structures. Examining the role of this technology in optimizing the production of objects in terms of desired structure and strength, minimizing material waste without altering weight, or even reducing weight, stands out as one of the foremost challenges faced by researchers. Additionally, investigating the proper adjustment of key parameters in the printing process to enhance the quality and precision of production represents another aspect of this technology. In this study, bio-degradable polylactic acid (PLA) filament, a popular material for 3D printing, was prepared as the primary material. Furthermore, in the part design section, one of the presented structures involved the use of sandwich structures with 3D Honeycomb cores. This structure contributes to the increased strength and resistance of these structures against impacts and stresses.The objective of this research is to combine the innovative design of components with 3D printers. Initially, the components were designed using Solidworks software, and then, with the expertise in this field, four printing parameters, including print speed, nozzle temperature, print angle, and layer thickness, were selected. Considering appropriate surfaces and determining four response variables, Fmax and Wt (the absorbed energy at the fracture point), as well as impact resistance resulting from two mechanical tests, 3-point bending and Charpy impact tests, conducted in the melting and welding workshop of the Iran University of Science and Technology. Subsequently, experimental designs were developed using Minitab software with the Taguchi method. An L9 orthogonal array was selected, and the experiments were repeated three times. After analyzing the results using regression, a regression equation was formed for each objective. By combining the regression equations with the ε-Constraint multi-objective optimization method, attempts were made to obtain optimal points. In total, 37 Pareto optimal points were obtained, and from the optimization results, the optimal values for the single-objective optimization factors were determined as follows: print speed (mm/min) 2950, nozzle temperature 210(°C), layer thickness 0.25(mm), and print angle 45 ±(°). In conclusion, the factors of print speed, print angle, layer thickness, and nozzle temperature were identified as the most influential on the response variables in the first to fourth positions, respectively. Overall, the use of a Honeycomb core sandwich structure in the design of a component resulted in a weight reduction of 15.57 grams, equivalent to 44%, compared to components without a sandwich structure. This reduction is highly valuable in terms of mechanical properties.
