Achieving dimensional control for fused deposition modeling (FDM) of polymericparts can be tedious and often involves inefficient trial-and-error experimentationthrough adjusting print parameters. These inefficiencies may be reduced through theuse of process modeling. Understanding the fundamental effects of the printconditions will facilitate predicting part dimensions as well as strength, accounting forthe degree of contact between roads, thermal history, and residual stresses.Modeling of additive processes is complex due to transient local boundaryconditions and a continually increasing part volume throughout the printing process.Numerous previous studies in FDM have focused on varying experimental processvariables such as print speed, extrusion, build temperatures, and print path todetermine their effect on mechanical properties. Fewer efforts, however, investigatethe complex thermo-mechanical history throughout the printing process or the drivingmechanism in road-to-road bonding due to local re-melting of previously solidifiedmaterial and diffusion.In this research, a 3D finite element model framework for predicting the thermaland residual stress history of an additively manufactured thermosetting polymer ispresented. By incorporating material sub-models with the Abaqus FEA solver, themodel is able to capture the cure kinetics during the printing process. The model takesa high-fidelity approach through the modeling and stepwise activation of individualroads to simulate the deposition process. Further, the geometry (i.e. cross-section) isvaried to demonstrate a mechanism capable of including future research road-to-roadbonding.
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