Build orientation optimization for extrusion-based additive manufacturing coupling with adaptive slicing

Additive manufacturing (AM) is an advanced technique to fabricate physical parts from 3D digital models layer-by-layer without geometry limitations. In existing AM processes, extrusion-based AM is popular, in which the material is extruded through the nozzle and moves on the platform according to the pre-defined toolpath. The part build orientation in AM has a crucial effect on the dimensional accuracy, surface quality, support structure, build time, and cost, etc. The layer thickness affects the surface quality and build time of an as-built part. It is preferable to optimize the build orientation and layer thickness simultaneously. This study proposes a build orientation optimization method for extrusion-based AM coupling with adaptive slicing. First, an adaptive slicing method using volume deviation rate is developed. Second, the estimation models of the relative decision criteria are created. In particular, the estimation model of surface roughness is constructed based on a designed benchmark artifact via the actual measurement by a contact surface roughness tester. Third, a set of alternative build orientations are generated based on the minimum bounding rectangles of the facet clusters in a manifold mesh model. Then, an integrated multi-criteria decision-making model composed of the weighted sum model and grey relational analysis is proposed to select an optimal build orientation among the alternatives above. At last, the effectiveness of the proposed method is experimentally validated using two case studies. The results show that the proposed method is desirable to simultaneously optimize the build orientation and layer thickness of parts in extrusion-based AM.