Framework for determining and simulating tensile properties of smart composite FDM printed parts

Abstract

Abstract : "Fused deposition modeling (FDM) is an additive manufacturing technique with good precision and moderate tolerances. Utilizing Finite Element Analysis (FEA) in literature is now key to studying the properties of these printed parts. The nature of the FDM process results in anisotropic inner structures with microscopic voids that are heavily affected by printing parameters. Even more so than the latter, composite coextrusion FDM printed parts possesses anisotropy due to the joining of the two filaments in the melt phase. These effects need to be examined and incorporated in an adequate digital twin. There exists a valid alternative to simulating this complex anisotropy, with the creation of Equivalent Homogenized Material. This study aims to bridge the gap between experimental data and FEA models for smart composite FDM parts. The goal is to establish a framework for determining effective homogenous mechanical properties of said parts. The Rule of Mixtures (ROM) method is first examined, and the limitations quickly become apparent, as the method fails to distinguish between two study cases with similar volume fractions but different fiber/matrix layouts. The second method, Representative Volume Elements (RVE), does not possess such a disadvantage. With an adequate convergence study on RVE size and fiber distribution, the calculated equivalent material’s properties show good agreement with experimental results, at a greatly increased computation cost."