Environmental Impact Assessment of Arburg Plastic Freeforming Additive Manufacturing

Arburg Plastic Freeforming (APF) is an advanced and original Additive Manufacturing (AM) technology that melts granulate thermoplastics through a heated reciprocating screw and deposits droplets layer-by-layer to build three-dimensional objects. The process requires technological decisions, the environmental repercussions of which are still unexplored. This study provides a parametric cradle-to-gate life-cycle assessment of the APF process based on the Ecoinvent dataset and the ReCiPe method. An application is presented to highlight the influence of different materials, process parameters and use scenarios. The findings show that printer utilisation is the most significant factor for all environmental impacts. Particularly, the machine production phase accounts for 67% of total impacts on human health, 35% on ecosystem quality and 85% on resource scarcity. The impact of electrical consumption on Global Warming Potential (GWP) makes the 3D printing phase crucial to human health (30%) and ecosystem quality (61%). Since both machine and 3D printing impacts are allocated on the building time, the influence of different materials and process parameters leads to considerable differences in impact indicators. Particularly, the different drop-aspect ratio determines a higher environmental impact of some biopolymers in comparison to oil-derived plastics. The sensitivity analysis demonstrated that the recycling of machine components and disposable plate significantly affects human health. Reusing building plates for more than one print job can bring additional benefits to resource scarcity. The proposed parametric framework can be effectively applied to assess the environmental impacts of any Arburg Plastic Freeforming production whose total mass and building time are estimated through calculation. These results establish a feasible and effective decisional method to find the most sustainable solution for the 3D printing of functional parts by comparing different sets of parameters.