Non-isotropic Material Distribution Topology Optimization for Fused Deposition Modeling Products

Mechanical properties of products produced with the Fused Deposition Modeling (FDM) process are known to be dependent on bead direction, especially when short fiber reinforcement is added to the polymer filament feedstock. As a result, the structural performance of fiber-filled FDM parts is expected to be improved by simultaneously computing preferred deposition directions while optimizing the internal support structure. This paper presents a topology optimization method for computing the material distribution within a fiber-reinforced polymer composite FDM part that incorporates the non-isotropic mechanical properties of the bead structure. Unlike the well-established homogenization topology optimization method which determines pointwise orthotropic properties by increasing the complexity of the design problem, our approach takes advantage of the simplicity of the SIMP method where the underlying orthotropic orientation is assumed. Computed results show the effect that the orientation of fiber filled bead orthotropic microstructure has on part topology for 2D FDM parts.