الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
3D printing techniques are becoming more common within several industrial fields
due to their many benefits. These benefits include customized properties of final
products, design independence, demand-driven manufacturing, waste alleviation,
and the ability to produce complex parts, as well as fast prototyping. Parts
manufactured using the powder bed fusion or material extrusion process are
achievable by various building parameters. In this investigation, a comprehensive
study was undertaken to clarify the variation in the compressive and impact strength
of SLS prepared Nylon Polyamide and FDM prepared polylactic acid plus,
polylactic acid (PLA) reinforced with carbon fiber (CF) and Nylon (PA) reinforced
with carbon fiber (CF) parts at different building parameters. Significant
methodological parameters were studied: infill patterns/layer layouts (triangular and
rectilinear), wall thickness (1.2, 3.6, 6mm) and infilled density (70, 85 and 100%),
utilizing material extrusion and powder bed fusion 3D printing machines. The
Central Composite Face-centered (CCF)method was applied to design an optimal
number of experiments. Experimental findings indicated that materials such as
polylactic acid plus, CF/polylactic acid Nylon, Polyamide12, and CF /Nylon
exhibited slightly different crashing patterns and mechanical behaviors when tested
for compression and impact. These tests informed the optimal printing parameters.
For PLA and PA 12 materials, these settings included an 85% infill, a 6mm wall
thickness, and a triangular infill pattern. In contrast, CF/PA material demonstrated
superior performance with a 100% infill, a 3.6mm wall thickness, and a rectilinear
infill pattern. Similarly, CF/PLA material achieved the most effective results with a
100% infill, a 6mm wall thickness, and a rectilinear infill pattern.
The best combination of each parameter is determined, and the 3D-printed tools are
fabricated accordingly. Finite element simulation is used to examine the 3D printed
tools for sheet metal forming. Finally, the 3D printed tools are used practically to
form steel sheets and the surface of the tools (punch and die) is optically scanned
after the forming operation. The results of optical scanning of 3D printed sheet metal
and stamps showed minimal deviations in both cases, with the deviations remaining
under 1 mm. For sheet metal, the largest DROP in DC01 was -0.3786 mm, while the
largest rise was 0.8859 mm. DX54D showed a significant DROP at -0.3066 mm and
a rise at 0.7559 mm. The use of white spray for optical scanning slightly increased
rising deviations. For stamps, the PLA dies used for forming DX54D sheet metal had the most significant surface DROP measured at -0.6825 mm after forming two
samples. The punches had smaller deviations. The PLA punch used for forming
DX54D sheet metal had the most dropping deviation of -0.4424 mm after forming
five samples. These results demonstrate the consistent quality and formability of all
3D-printed samples.