Design of an Innovative Three-Dimensional Print Head Based on Twin-Screw Extrusion

This paper presents the embodiment design of an interchangeable print head based on twin-screw extrusion, specially developed to allow in-process multimaterial mixing and direct deposition of the product to structure three-dimensional (3D) parts. The print head focus on research applications with middle-end 3D printers. Commercial extrusion-based 3D printers have limited applicability due to the scarce variety of plastic filaments available. In that context, one important trend for the advance of additive manufacturing (AM) is the design of systems capable of using alternative material types in different states. The systematic process is presented as a case study and brings together concepts from mechanical design and polymer processing. The main contribution of this paper is to provide general guidelines to be used on similar projects, in view of the crescent demand for more adequate and flexible additive processes.