Abstract
3D printing, using fused deposition modeling (FDM) has become a staple in the prototyping process because it allows engineers and designers to manufacture parts within a matter of hours instead of days. FDM printing works by melting and extruding plastic filament through a heated nozzle to build a 3D object layer by layer. However, due to the nature of the additive process, parts often fail when placed under loads that they might be subjected to during testing; especially when the loads are applied to the specimen perpendicular to the layer lines. These failures often slow down or halt the iterative engineering process. This work aims to explore strengthening 3D printed parts using an electroplating process typically used to add conductive properties to the plastic material. Tensile testing dog bones that comply with ASTM D638 were printed using an off-the-shelf FDM printer. Specimens were printed parallel to the build plate, at a 45-degree angle from the build plate, as well as perpendicular to the build plate using both non-conductive Polylactic Acid (PLA) filament as well as conductive PLA. Specimens printed in the non-conductive PLA were manually painted with a conductive paint prior to electroplating. Conductivity tests were completed on the specimens before the electroplating process to study its effect on the process. The printed specimens were then subjected to an abrasive sanding process to aid in adhesion of the thin metal layer desired followed by a cleaning in distilled water. The electroplating process requires submerging the specimen to be electroplated as well as the desired metal in an electrolyte solution for an extended period. The specimens will act as an anode and be wired to the negative terminal of a power supply while the desired metal will act as the cathode wired to the positive terminal. Using a single column tensile tester, the specimens were subjected to the testing method provided in ASTM D638 to find the maximum load at failure for all the samples. A statistical analysis was conducted and found that difference of tensile strengths existed between the electroplated and non-electroplated parts where the electroplated parts were on average 20% weaker. While electroplating did not strengthen the 3D printed parts it did add conductive properties to them which gives designers more options when that is a property desired.
