A Feasibility Study of Lightweight Polylactic Acid Fused Deposition Modeled Propeller Prototyping

Abstract

From the inception of fused deposition modeled (FDM) 3D printing, various materials have been introduced as filaments. Lightweight polylactic acid (LW-PLA) has been introduced as a 3D printing material by a company named ColorFabb, and it has a unique property to expand at around 230℃. The expansion can be calculated and harnessed to create more lightweight 3D printed models. Previous studies have used ANSYS computer simulations to gauge the feasibility of 3D printed propellers of various materials. Previous studies that tested propellers in real life have shown that propellers made from polylactic acid (PLA), another 3D printing plastic, are only feasible for prototyping purposes. This study attempted to find feasibility of LW-PLA in the FDM prototyping of propellers by using a real life testing apparatus to compare LW-PLA and PLA propellers. 4 propeller designs were made, and PLA and LW-PLA counterparts were created for each design. A significant difference in thrust-efficiency ratio was found between LW-PLA and PLA propellers, indicating that LW-PLA propellers were not feasible for propeller prototyping. It was observed that the application of acrylic sealer coatings to both LW-PLA and PLA propellers decreased the difference, but the difference was still significant in most cases. Additionally, LW-PLA propellers were observed to be about 50% of the weight of their PLA counterparts, indicating that LW-PLA propellers may be useful in situations where weight is required to be minimized. This study is significant in that it addresses the major gap in the research of LW-PLA and its applications in aerospace.