Assessment of the cartesian and layered tetrahedral mesh strategies in the thermomechanical simulation of the selective laser melting process

Selective Laser Melting (SLM) is an Additive Manufacturing (AM) process aimed for the fabrication of complex metallic parts. Due to the inherent to the process rapid thermal cycles and the developed high temperature gradients, residual stresses are formed which result to part distortion and may lead to preliminary failure during its building. Current thermomechanical modelling methods of the SLM process aim at the prediction of residual stress and strain fields in an efficient manner. Meshing schemes such as uniform or adaptive cartesian and layered tetrahedral meshing have been utilized in thermomechanical modelling but their accuracy has not been evaluated yet. The present study quantitively assess the meshing strategies in the simulation of SLM process with the focus placed on the characteristics of layered tetrahedral meshing. Although it is shown both meshing strategies lead to accurate results for a relatively small element size, layered tetrahedral meshing strategy can achieve convergence with relative coarse mesh and better discretization of curvature regions.