Large-format polymeric pellet-based additive manufacturing for the naval industry

Polymeric Pellet-Based Additive Manufacturing (PPBAM) systems are increasing in the field of 3D printing as a result of the evolution of additive technologies as their development process consolidates and expands. New opportunities for industrial integration of additive manufacturing (AM) technologies are identified, including AM of large polymeric parts. The PPBAM process consists of adapting a pellet-fed extrusion mechanism to a displacement system, either a Cartesian mechanism or a robotic arm system, building parts in a multi-layered approach. This use is justified by the extruded filament sizes required and the material costs when facing large-format prints. In this article, a pellet extrusion based printer prototype is presented together with a case study. The case study consists of the development of a two cubic meter capacity plastic part for the naval industry with a topology optimization design approach and material selection and validation methodology for a large-volume pellet based extrusion system. Two functional prototypes were developed with the selected materials from the explained methodology a PLA and a flame retardant ABS, and post processed to full fill the actual product´s specifications.