QUALITY ASSURANCE OF PARTS MADE OF NYLON OBTAINED BY FUSED DEPOSITION MODELING

Purpose. A comprehensive study of the Fused Deposition Modeling (FDM) process parameters influence on the surface roughness of parts. Research methods. The samples for research were produced by the FDM method on a Profi+midi 3D printer. Slic3rPE software were used for CAD model slicing and G-code preparation. The samples were printed using Nylon filament from the Plexiwire company. Drying of the material before printing was carried out in the ELEKTROTERM electric furnace. The 171621 profilometer was used to determine the roughness of the samples. The STATISTICA software package was used for statistical processing of the results. Results. The influence of different combinations of FDM process parameters on the surface roughness of parts was examined. Surface roughness was found to be most influenced by the following interactions: printing speed and bed temperature, layer height and infill density, layer height and printing speed, layer height and extrusion multiplier, extrusion multiplier and number of shells and layer height and number of solid top and bottom layers . In addition, the following factors separately affect the roughness: infill density, infill pattern, extrusion multiplier and extrusion temperature. Scientific novelty. A rational combination of FDM process parameters has been determined at which the minimum surface roughness is achieved. Thus, it was determined that the roughness has a lower value at a rectilinear infill pattern, and at a infill density of 25 %, an extrusion multiplier of 0.9, an extruder temperature of 265 °C, a printing speed of 40 mm/s, a layer height of 0.15 mm, a number of solid layers of 2 and a platform temperature of 100 °C, the roughness value decreases. If the bed temperature and printing speed are increased, the roughness value will increase, as will the layer height and infill density. Increasing the extrusion multiplier or decreasing the extruder temperature have a negative impact on the surface roughness. All other parameters had almost no effect on surface roughness. Practical value. The results of the study make it possible to predict and improve the quality of nylon parts produced by FDM due to establishing optimal process conditions.