Anisotropic Finite Element Modeling of the Fused Deposition Modeling Process

The exhibited material behaviors of 3D printed Acrylonitrile Butadiene Styrene (ABS) plastics are highly dependent on the load direction with respect to print orientation. A database of strength characteristics was generated to facilitate the construction of a Finite Element Analysis (FEA) model. This model was used to predict the anisotropic material properties of ABS under load conditions. It was demonstrated that an FEA model for 3D printed ABS plastic can be created and verified by measuring the material properties of test specimens printed in multiple orientations. An accurate FEA model of the anisotropic material properties of ABS can be used to predict the behavior of the part under load conditions. Anisotropic material properties become an issue when printed parts are used as an end product. A load applied to a part parallel to the print direction may not result in fracture, while the same load applied perpendicular to the print direction may result in catastrophic failure. Predicting these behaviors is paramount when designing parts designated for 3D printing, particularly when used as a "fail safe" to protect more expensive components in a drivetrain as noted below.