Optimization of process planning for reducing material waste in extrusion based additive manufacturing

Among the available additive manufacturing technologies, extrusion based 3D printing (otherwise known as fused deposition modelling or fused filament fabrication) is among the most commonly used due to low cost and relative simplicity. However, such printers still suffer from redundant support material waste (both interior and exterior) when printing large-volume solid objects or objects with overhangs. The support material can also be a significant cause of long part production time and higher energy consumption during manufacture. Hence, we propose a new support generation strategy considering both interior and exterior support via AM process planning to reduce the total amount of material consumption, production time and energy consumed for manufacturing an object. Print path and print orientation are both considered as significant factors and are both optimized for achieving the lowest consumption of material. The areas to be filled on each layer are determined according to the printable threshold overhang angle (PTOA) and the longest printable bridge length (LPBL). The characteristics of LPBL and PTOA are fully considered for saving more material. Several tests are used to verify the proposed strategy and the results show that this strategy can considerably reduce material waste, production time and energy consumed compared with conventional strategies, enabling AM to be a more environmentally friendly and sustainable manufacturing technique.