Modeling of Manufacturing Induced Residual Stress in 3D-Printed Components

The objective of this work is to model the residual stresses that can arise during the production of components using fused deposition modeling (FDM). Thermally induced residual stresses occur during the manufacturing process due to unfavorable thermal conductivity of the polymers used. For this purpose, the G-code of a 3D printer is first imported into a column interpreter which can be rearranged according to given requirements. This is done using a Visual Basic macro. This geometry data is further processed using a CATIA macro to create a geometry in CATIA. For simplification a circular profile is used, which is extruded over polymer lines and stacked on top of one another. In concert, the time-varying assignment of the boundary conditions over which the printing process is simulated is performed. The calculations are made in ANSYS Workbench using ANSYS APDL commands. The element activation-deactivation method is used for the simulation. The thermal simulation is first demonstrated and validated on a sample block and then transferred to the CAD part. The results are imported from Transient Analysis and used as load steps for the Static Structural Analysis, where stresses, strains, and deformations are calculated. The results are then studied to finally print the geometry.