Dynamic characterization of off the shelf polymer composites printed with fused deposition modeling

Fused deposition modeling (FDM) is the most common and cost effective form of additive manufacturing (AM). Due to the ubiquity of the approach, a range of off the shelf composite materials have been developed by companies, often with the goal of improving the printed part's physical appearance or increasing or decreasing the weight of the part. These composites typically have a base material of a standard FDM printed polymer, with additives such as metal particulates or lightweight filler added. This study will examine the dynamic properties of a set of off the shelf materials to characterize acoustic sound speed, complex elastic moduli, and loss. All of the materials in this study have a base material of polylactic acid (PLA) making it possible to easily print them into multi-material structures. The filler materials showed minimal impact on some viscoelastic properties but resulted in significant changes in acoustic sound speed. Characterization of this type is a critical component in development of an expanded database of material properties for use in design.