Ultrasonic Rapid Manufacturing of Meso/Microscale Functional and Active Structures

Tufts University, Medford MA

Investigators

Abstract

This program will introduce and analyze a new rapid manufacturing technology for fabrication of functional miniature devices with integrated intelligent structures and encapsulated components. This will be based on the ultrasonic welding (USW) process, a solid-state, cold joining technique, yielding strong bonding between dissimilar metals and other materials. Ultrasonic rapid manufacturing (URM) will utilize multiple material foils and fibers, that will be bonded in subsequent layers, followed by ultrasonically assisted diamond scribing to the proper contours. Fundamental understanding and comprehensive modeling of microscale USW, will be addressed by a hybrid experimental and computational process analysis. Extensive characterization of the joint structure and properties of aluminum bonds to other selected metal alloys will be performed in the laboratory. Knowledge gained from this research will define optimal process conditions, allow intensive study of microscale material effects, making it accessible through incorporation in a continuous ultrasonic transformation database. Numerical simulation of the interdependent mechanical, thermal and diffusion distributions during the USW process will be conducted in concert with the experimental work. Researchers at Tufts University and Northeastern University will collaborate on this project. This URM research will be connected with the engineering curriculum to leverage rapid manufacturing education. This will be promoted by a new undergraduate/graduate course on Rapid Prototyping, Tooling and Manufacturing, as a basis for a future Rapid Manufacturing minor; a new SFF and Microfabrication Seminar series with invited industry experts; and an annual Rapid Manufacturing Contest for undergraduate student groups nationwide. The program will involve close collaboration of the partnering institutions. Industrial sponsorship through in-kind equipment and technical support will also be provided by Axcelis Technologies, Honda R&D Americas and Stapla Ultrasonics. The benefits of the new technology will be harnessed in the design and fabrication of miniature multi-material internal structures, with embedded prefabricated elements (sensors, actuators, processors, MEMS etc), providing multi-domain functionality in mechatronic, optoelectronic, microfluidic, biomedical microdevices etc.