Design of an innovative new extrusion system for a printing machine for ceramics

Additive manufacturing (AM), also known as 3D printing is a manufacturing technology that takes the information from a computer-aided design (CAD) and builds parts in a layer by- layer style. Further to the extensive research on 3D printing of polymers and metals, ceramics have attracted the increasing attention of researchers, in sectors such as aerospace, electrical, chemical or medical. Complex shapes printing with porous structures, which are required in the medical area for prostheses, is difficult with most of the traditional manufacturing processes. However, additive manufacturing processes can achieve such geometries. Specifically, the direct ink writing (DIW) process is one of the most promising and inexpensive techniques for shaping free-form ceramic components. In this process, the material is extruded through a syringe and then deposited on a printing bed. In the present paper the redesign of an extrusion head for ceramics is presented. The main disadvantage of the original design was the limited volume of the syringe vessel barrel. For this reason, the proposed new system has higher capacity. For that, first the target specifications of the new extrusion system for larger material quantities were defined. For this purpose, the Quality Function Deployment method was used, in order to assure the required quality from the design phase. Then, these critical features and specifications were used to generate the different concepts that will ensure the quality of the printed parts when printing large volumes. The morphological matrix was used in this case. The work presented in this paper is the starting point of the development of the final design of an innovative extrusion head.