This proposal seeks to develop novel 3D printing (also called additive manufacturing) technology for a broad range of microwave frequency applications including wireless communication, remote sensing, high speed computing, etc. Although it has been argued that 3D printing could be the future of manufacturing, the potential and applicability of these methods for creating functional electronics, especially those operate at RF / microwave frequency which are critical components for many applications remain largely unexplored. A number of limitations need to be resolved before advanced microwave components and systems can be printed in a 3D fashion robustly. Among them, the lack of printable materials with desired microwave properties and the challenges in integrating high quality conducting constituents are some of the main issues. This proposed research will explore several novel ideas to address these outstanding issues of additive manufacturing for microwave applications. The proposed work will contribute timely to the additive manufacturing field and enable 3D printing of fully functional microwave components and systems. This research will also have significant broader impacts to the advancement of science, engineering and human society. The research results will contribute to novel aspects of next generation of manufacturing technology and advance the state-of-the-art of 3D printed microwave electronics. The expected outcome may enable fully customizable, high value, multi-functional products for the consumer, biomedical, aerospace and defense industries. A concurrent and integrated research education plan including active participation of both graduate and undergraduate student researchers will also be carried out. Engineering curriculum will be enhanced not only at the two participating universities but also for the bigger community through a new course and new textbook on Additive Manufacturing Technology (to be offered online as well as in classrooms), open research seminars, and undergraduate senior Capstone projects. The proposed education program will provide a broader education scope in the society by holding regular classroom / industrial seminars and attending technical conferences. Moreover, outreach to underrepresented groups will be emphasized specifically targeting women and minorities at both universities and at local K-12 schools. It is expected that the proposed education component will provide timely training of work force in advanced manufacturing which is of great national importance.
The objective of the proposed research is to advance additive manufacturing technology to enable 3D printing of microwave components and systems. Most of the materials used in 3D printing technology currently are designed or selected with only mechanical property in mind, thus limiting their applicability to microwave applications. While conductive ink printing has been widely applied, the high temperature annealing process required is often not compatible to the non-conducting part of the objects to be manufactured. In this program, 3D printable materials with robust electromagnetic properties will be investigated and developed based on a novel polymer matrix compound technique to obtain improved EM properties such as larger range of dielectric constant and magnetic response. 3D printing technique for additive manufacturing of high quality (i.e., good RF conductivity) conductors by ultrasonic or thermal embedding and laser welding metallic wires and fine-pitch meshes within materials such as thermoplastics will be developed and refined. Based upon these new techniques, practical microwave components (i.e., transmission line with vertical interconnects, wire and patch antennas, etc.) will be designed, printed and tested. In addition, novel 3D gradient index (GRIN) metamaterial-based device (i.e., a flattened Luneburg lens imager) with superior performance will be investigated.
