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FDM 3D Printing Process - Risks and Environmental Aspects

The application of the 3D printing processes is continuously increasing due to their large number of technical and economic advantages when produce prototypes, but in the mass fabrication as well, especially for metal printing of low dimension products. The process produces pollution as all technological processes. Noise, fume and polymer wastes are the main elements which exit from the process and they are not products. The types and the volumes of those pollution emissions depend on the process parameters. The paper presents the results of FDM process emissions analysis. It was recorded the noise for different stages of the printer functioning. It was measured the volume and the contents of the fume produced during the extrusion of the polymer, for PLA polymer and for ABS polymer filaments. Specific risks were analysed and conclusions were reported. The measurement was done for a random chosen product and the results were compared with the pollutant emissions from traditional technological processes applied to erect the same type of product. It has been concluded that the noise emitted during the FDM printing is about 82-85% of the noise produced when apply milling to create similar shapes and dimensions (it was recorded values for the sound pressure in a large range: 42-68 dB, depending on the working regime). Regarding the fume emission, the intensity of emission was up to 40% higher in the FDM process comparing to the milling process. That was explained as being a direct result of the fluid-viscous state in which the material is put during the printing process. When discuss about the risks, most of the main identified risks in the milling and/or extrusion process were almost inexistent in the FDM printing. Electrical injuries and heat injuries are the main risks to which the operator is exposed. Mechanical injuries are sensitively lower than in the traditional processes, as milling The FDM process is safer and produces lower material wastes. It can be concluded that the FDM printing process has lower impact with the environment and with the operator.