| description abstract | Although extrusion-based 3D printing processes have seen many successful applications at the macroscale, it has proven to be challenging for consistent, repeatable, and cost-effective printing at the microscale due to its dynamic complexities. To fully tap into the promise of microextrusion printing (µEP) of fabricating fine resolution features, it is critical to establish an understanding of the fundamentals of ink flow, interface energy, drying, and the process-property relationship of the printing process. To date, a comprehensive and coherent organization of this knowledge from relevant literature in different fields is still lacking. In this paper, we present a framework of the underlying principles of the microextrusion process, offering an overall roadmap to guide successful printing based on both results in the literature and our own experimental tests. The impacts of various process parameters on the resolution of printed features are identified. Experiments are carried out to validate the developed framework. Key challenges and future directions of microextrusion 3D printing are also highlighted. | |