Impact of 3D printing patterns and post-consolidation pressure on mechanical properties of FDM printed samples
Abstract
The Additive Manufacturing (AM) technology originally was invented as a rapid prototyping appliance for exposition and validation of
designs. The recent advancement of AM technologies, such as Fused Deposition Modelling (FDM), is driving it from rapid prototyping to rapid
manufacturing. Nevertheless, constructing end-user functional parts using FDM believed to be a challenging job. The complication arises from
the large number of processing parameters that affect the final part design such as: building direction, hot end temperature, layer height, infill
pattern and more. The processing parameters of FDM effect the quality of the parts and their functionality. In addition, a more meticulous
understanding is required to elaborate on the impact of the FDM processing parameters on the final part’s mechanical properties, dimensional
accuracy and building time. This experimental study investigates the effect of filling pattern on tensile, flexural and Impact strength of the parts
printed via fused deposition modeling (FDM), 3D printer. The main downside of the printed products, with an FDM 3D printer, is the low strength
compared to the conventional processes such as injection molding and machining. The issue stems from the low strength of thermoplastic
materials and the weak bonding between deposited raster’s and layers. Selection of proper filling pattern and infill percentage could highly
influence the final mechanical properties of the printed products that were experimentally explored in this research work. Concentric, rectilinear
with raster angle 90 and 45, and honeycomb patterns and filling percentage of 60 were the variable parameters to print the parts. A total of 68
test specimen samples were printed using varying processing parameters. To investigate the repeatability and tolerances, test series includes a
minimum of five to seven test specimens. The results indicate that concentric pattern yields the most desirable impact and flexural strength, at
all filling percentages, apparently due to the alignment of deposited raster with the loading direction. Tensile strength is greatly observed in the
rectilinear with raster angle 90 (transverse printing pattern), thanks to the linearly deposited layers
