Thermal finite element simulations for extrusion-based additive manufacturing processes

Additive manufacturing techniques facilitate the consideration of advanced geometrical and functional properties of components. However, optimizing the process parameters to reduce distortions or residual stresses in the final part is quite difficult. This is due to the enormous number of processing parameters, which might even affect each other. To circumvent time- and resource-consuming experimental tests, simulations can be applied to estimate the component properties after manufacturing. In this contribution, a consistent approach for thermal finite element simulations of additive manufacturing processes is provided. The process information, which is stored in the G-code, is used to perform an interpolation of the process path that is then utilized for both the element activation with an element-birth technique as well as the movement of a heat source. Because of the continuous path interpolation, even curvilinear paths can be employed for the element activation. Further, the heat exchange with the environment by radiation and convection is considered as varying interface boundary conditions on the component’s structure during the process. The suitability of the explained element activation technique is shown for different numerical examples of extrusion-based additive manufacturing processes.