A review on droplet-based 3D printing with piezoelectric micro-jet device

Abstract The droplet-based 3D printing with piezoelectric micro-jet device (PMJD), also known as fabrication with droplet ejection, has shown its unique advantages exceeding typical processing in direct rapid manufacturing (DRM) of miniature and complicated metal parts, function components, and other heterogeneous devices. Recently, the droplet-based 3D printing with higher printing velocity, controllable precision and smaller printing volume is need more and more in additive manufacturing (AM) fields, which promotes the development of the droplet-based printing technology to a faster, accurate and flexible direction. In this regard, the droplet-based 3D printing with PMJD has received a lot of attentions from universities, enterprises, and other research institutes. In this review, based on introducing the droplet-based 3D printing technologies, we will clarify the advantages of droplet-based 3D printing, especially the droplet ejection with PMJD. Then, the connections and differences between the ejection of non-metallic droplets and metal droplets based on piezoelectric micro-jet are also clarified, meanwhile, the challenges, such as the consistency, reliability, and stability of piezoelectric actuated droplet ejection, are concluded and analyzed. In general, the future developments of droplet-based 3D printing technology are prospected, and the review can provide some further references for the related works.