Design for Sustainable Additive Manufacturing (DfsAM): Preperation and Validation of a Transversely Isotropic Simulation Model for FFF Components Made from Virgin and Recycled Polypropylene Filaments

Simulation modeling takes up an important role in virtual product development in terms of cost and time improvement. Due to the anisotropic characteristics of the Fused Filament Fabrication (FFF) process, material models with bulk properties for Finite-Element-Analysis (FEA) lack accuracy. This problem was addressed in this research by tension (DIN ISO 527) and compression (DIN ISO 604) tests of polypropylene and elastic polypropylene filament for FFF in 0° and 90° printing directions. Furthermore, a recycling cycle for both filaments was carried out and reassessed. Based on the test results a transversely isotropic material model with bilinear hardening was generated and validated for the standard polypropylene filament with a three-point bending test (DIN ISO 178). The material model was capable of reasonably simulating the component behavior for the complex load scenarios up to a strain of 15 %. The combination of a cost, time and resource-saving simulation approach with a circular material strategy proposes a way for fusing performance and sustainability in the field of Additive Manufacturing (AM). The combination of recycling processes and material models, both assessed and verified experimentally, respectively, will help adapt the product geometry to the material properties modified from recycling.