FFF-based Metal and Ceramic Additive Manufacturing: Production Scale-up from a Stream of Variation Analysis Perspective

Metal and ceramic fused filament fabrication (FFF) has been increasingly used additive manufacturing (AM) processes in the various applications including product prototyping and rapid tooling. Due to its high flexibility in both material composition and part design fabrication, metal and ceramic FFF has shown significant potential in fabricating various functional structures with specific properties of interest, such as mechanical property and thermal conductivity. Moreover, those FFF processes have also demonstrated phenomenal advantages over the other AM technologies, including its cost and energy efficiency. However, the quality control for these processes is still in its infancy, which hinders their broader adoption in more mission critical applications. Therefore, there is an urgent need in understanding the process-structure-property relationships in the metal and ceramic FFF. Both metal and ceramic FFF processes are generally composed of three major steps, i.e., materials preparation, FFF, and post-treatment. In this paper, the state-of-the-art studies on metal and ceramic FFF has been examined from a stream of variation (SoV) analysis perspective, where the variation sources introduced in each step are investigated and the metrological methods to characterize those variation are summarized. Furthermore, research opportunities and challenges for the quality control for the production scale-up of the FFF-based metal and ceramic AM are discussed. (c) 2023 The Authors. Published by ELSEVIER Ltd. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0)