The Effect of Recycled Materials and Adhesion Angle on the Tensile Strength of Additive Manufacturing

As 3D printing technology has advanced, the cost of 3D printers has dramatically decreased, however the cost of the filaments used in the printers has remained virtually the same.  My senior thesis has focused on building a filament extruder and testing the tensile strengths of 3D printed plastics (PET ‘Polyethylene terephthalate’ , ABS ‘Acrylonitrile butadiene styrene’ and PLA ‘Polylactic acid’). Both PLA and PET plastics can be extruded into a filament and be reused by a 3D printer, but ABS couldn’t be recycled for this project because it requires air-handling systems to prevent toxic fume inhalation during filament reforming. After the materials were printed, a tensile test was run on the materials to measure the strength of the recycled plastics versus non-recycled samples and the strength of different layer adhesion angles. The three different adhesion angles that were selected were a flat print with an angle of 0°, a vertical print with a 90° angle, and a print on a 45° angle. Layer adhesion is one of the most important factors in additive manufacturing because it defines how well each layer sticks to one another. Therefore, this project will show the effect of how both different angles relative to the print bed effect the strength of a 3D printed object, and how recycled materials can be used in 3D printing. This project will hopefully allow future students of Union College to have more opportunities to use both recycled materials and 3D printing in their projects.