Feasibility Study of an Extrusion-based Direct Metal Additive Manufacturing Technique

A new extrusion-based additive manufacturing technique is described in this paper together with the main components of the machine capable of carrying out the process. Innovative characteristics of the machine are the fixed extrusion head and the workpiece moving thanks to a 5-axis parallel kinematics handling system, allowing the capability of inclining the part during the material deposition and consequently avoiding support structures. The extrusion head and nozzle have been designed in order to be able to extrude high viscosity mixtures with low polymeric content. Preliminary tests prove that a good final density can be obtained after de-binding and sintering and that it is possible to achieve a good bonding of extruded and deposited wires in case of AISI 630 stainless steel.