Исследование прочности 3D-печатных изделий при варьировании технологических параметров в процессе печати

Abstract

The technology of additive manufacturing of parts makes it possible to signifi cantly reduce the cost of machinery repair. However, the property formation laws of such parts have not been suffi ciently studied. The authors have studied the relationship between the ultimate strength of 3D-printed samples and the number of wall layers and infi ll density. Samples produced according to GOST 11262-2017 by 3D printing using FDM technology from ABS plastic were tested for static stretching. Two groups of samples, diff erent in technological parameters of 3D-printing, were made. In the fi rst group the wall of the samples was formed in four layers, the density of the sample fi ll varied in the range of 20 to 100%. In the second group, the number of wall layers varied from 2 to 10, the infi ll density of the samples corresponded to 33%. When samples were made, extruder temperature was 230°C, table temperature - 110°C, layer height - 0.15 mm, and printing speed - 60 mm/s. An analysis of the yield strength of the samples showed an increase in strength with an increase in the number of wall layers. Signifi cant diff erence of strength values was observed in samples with six layers and more. Signifi cant variation of yield strength values can be explained by the presence of defects in the samples after printing. When infi ll density exceeded 40%, a signifi cant increase in strength was observed due to the densifi cation of polymer molecule bonds. In the range of 20 to 40%, the strength index did not change, because the same structural changes occurred in this range. It was found that the number of wall layers should not exceed the number of inner perimeter layers and the infi ll density of the parts should be 100% to produce polymeric parts of agricultural machinery by 3D printing using FDM technology with maximum strength characteristics.