# Sustainable Manufacturing Decisions through the Optimization of Printing Parameters in 3D Printing
## 1 Introduction  
In recent years, the characteristics of additive manufacturing, such as net shape and design flexibility, have resulted in rapid growth in the manufacturing industry. Fused filament fabrication (FFF) possesses rapid prototyping [1, 2], caters to different materials [3], eliminates post-processing procedures [4, 5], and requires a short processing time [6, 7]. Moreover, its competitiveness can be enhanced by continuously improving printing quality [8, 9]. In addition, due to the increase in sustainability issues, the efforts to reduce energy consumption [10], air pollutants [11, 12, 13], and manufacturing costs [14] can result in increased adoption of sustainable manufacturing. Dimensional accuracy is a significant factor for quality verification. In FFF printers, there is a significant correlation between printing parameters and dimensional accuracy. For instance, nozzle temperature changes can affect the homogeneity of extruded materials and cause printing size variations. [PERSON] et al. [15] proposed that nozzle temperature can affect the dimensions of printed objects. For instance, when the nozzle temperature was set to 190 \({}^{\circ}\)C, the dimensions of printed products were more accurate. [PERSON] et al. [16] found that support structure uniformity also affects dimensions, which could be optimized by adjusting the nozzle aperture and Z-axis height. [PERSON] et al. [17] stated that layer thickness, air gap, raster angle, build orientation, road width, and a number of contours directly impact object dimensions. Moreover, they demonstrated the nonlinear relationship between printing parameters and dimensional accuracy through an I-optimality criterion and then used the desirability approach to obtain optimal printing parameters. In additionto dimensional accuracy, the mechanical properties of printed objects also affect quality. [PERSON] et al. [18] performed mechanical strength tests on printed objects with different nozzle sizes and layer thicknesses, and the results showed that a larger nozzle aperture can lead to an increase in the strength of a printed object under the same layer thickness. From the perspective of energy consumption in sustainable manufacturing, [PERSON] et al. [12] and [PERSON] et al. [19] found that most of the overall energy consumption is attributed to heating and maintaining the temperature of the nozzle/build plate. [PERSON] et al. [20] showed that the changes in layer thickness, printing speed, fan rate, and infill density also affect energy consumption. These studies point to a significant correlation between dimensional accuracy and energy consumption and show that both of them are affected by the same printing parameters. The ultimate goal of sustainable manufacturing is to consider quality, environmental impact, cost, and even social issues together, causing a change in the optimization goal. [PERSON] et al. [15] used the Taguchi method to study the relationship between the printing parameters and mechanical properties of printed objects, including dimensional accuracy, tensile strength, yield strength, and ductility. The results showed an inverse relationship between dimensional accuracy and mechanical strength. Thus, optimal parameters cannot directly yield the maximum mechanical strength and minimum dimensional tolerance. [PERSON] et al. [12] indicated an inverse relationship between printing quality and energy consumption. To improve printing quality, more energy is consumed. Conversely, reducing energy usage results in poorer quality. Using the Taguchi method, [PERSON] et al. [21] explored an optimization study of the cost and time of printing (by filament usage) and concluded that multiobjective optimization results vary with respect to different weights. [PERSON] et al. [22] used grey relational analysis to study printing time and material usage and obtained optimized printing parameters.