Effect of 3D Printing Process Parameters on Mechanical Properties of Printed Parts

Lee, Lit Phin (2019) Effect of 3D Printing Process Parameters on Mechanical Properties of Printed Parts. Final Year Project (Bachelor), Tunku Abdul Rahman University College.

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Abstract

In the past decades, 3D printing method is one of the most popular solid free form techniques. Currently, most of the research is focusing on improving the quality or mechanical properties of thermoplastic polymer fabricated by traditional Fused Deposition Method (FDM). Therefore, more quantitative investigations need to be carried out to determine the optimize parameters of the extrusion-based 3D printing. In this research, Polylactic acid (PLA) material filament is used to fabricate or print the parts in few different process parameters, including layer thickness and printing speed, then investigate the mechanical properties of each part. PLA filaments were chosen due to easier to print and safety reasons. FDM type printer is used in the research. These printed parts are tested on various mechanical properties tests respectively, including Tensile Test and the Izod Impact Test. From the results of the tests, we can conclude the mechanical properties, including tensile strength, Elastic Modulus and energy absorb of the printed parts of each printing process parameters. The aim of the research is to determine best printing process parameter, including layer thickness and printing speed for 3D printed parts printed by Weistek WT280X Speed 3D Printer, in term of achieving the most desired performance in respective mechanical properties. From the research, between range of layer thickness from 200-μm to 300-μm and printing speed ranged from 20 mm/s to 90 mm/s, the increase of printing speed of certain layer thickness, will increase the Ultimate Tensile Strength of the parts, due to the adhesion between filaments constituting infill is better and also the filament layers has less time to cool down between each passage. However, from the stress-strain curve graph, increase in printing speed for a certain layer thickness will reduce maximum elongation and increase the Elastic modulus of the printed parts. Besides that, increase of layer thickness not only will decrease the maximum elongation and increase the Elastic Modulus of the parts, but increase the Ultimate Tensile Strength of the parts due to increments of Inter-Fiber Bonding Region. Besides that, increases in layer thickness will also increase both energy absorbed, and energy absorbed per unit area, achieving the objectives of determining most optimum layer thickness in impact energy absorption. V